literature searches research method

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• v.106(4); 2018 Oct

A systematic approach to searching: an efficient and complete method to develop literature searches

Associated data.

Creating search strategies for systematic reviews, finding the best balance between sensitivity and specificity, and translating search strategies between databases is challenging. Several methods describe standards for systematic search strategies, but a consistent approach for creating an exhaustive search strategy has not yet been fully described in enough detail to be fully replicable. The authors have established a method that describes step by step the process of developing a systematic search strategy as needed in the systematic review. This method describes how single-line search strategies can be prepared in a text document by typing search syntax (such as field codes, parentheses, and Boolean operators) before copying and pasting search terms (keywords and free-text synonyms) that are found in the thesaurus. To help ensure term completeness, we developed a novel optimization technique that is mainly based on comparing the results retrieved by thesaurus terms with those retrieved by the free-text search words to identify potentially relevant candidate search terms. Macros in Microsoft Word have been developed to convert syntaxes between databases and interfaces almost automatically. This method helps information specialists in developing librarian-mediated searches for systematic reviews as well as medical and health care practitioners who are searching for evidence to answer clinical questions. The described method can be used to create complex and comprehensive search strategies for different databases and interfaces, such as those that are needed when searching for relevant references for systematic reviews, and will assist both information specialists and practitioners when they are searching the biomedical literature.

INTRODUCTION

Librarians and information specialists are often involved in the process of preparing and completing systematic reviews (SRs), where one of their main tasks is to identify relevant references to include in the review [ 1 ]. Although several recommendations for the process of searching have been published [ 2 – 6 ], none describe the development of a systematic search strategy from start to finish.

Traditional methods of SR search strategy development and execution are highly time consuming, reportedly requiring up to 100 hours or more [ 7 , 8 ]. The authors wanted to develop systematic and exhaustive search strategies more efficiently, while preserving the high sensitivity that SR search strategies necessitate. In this article, we describe the method developed at Erasmus University Medical Center (MC) and demonstrate its use through an example search. The efficiency of the search method and outcome of 73 searches that have resulted in published reviews are described in a separate article [ 9 ].

As we aimed to describe the creation of systematic searches in full detail, the method starts at a basic level with the analysis of the research question and the creation of search terms. Readers who are new to SR searching are advised to follow all steps described. More experienced searchers can consider the basic steps to be existing knowledge that will already be part of their normal workflow, although step 4 probably differs from general practice. Experienced searchers will gain the most from reading about the novelties in the method as described in steps 10–13 and comparing the examples given in the supplementary appendix to their own practice.

CREATING A SYSTEMATIC SEARCH STRATEGY

Our methodology for planning and creating a multi-database search strategy consists of the following steps:

• Determine a clear and focused question
• Describe the articles that can answer the question
• Decide which key concepts address the different elements of the question
• Decide which elements should be used for the best results
• Choose an appropriate database and interface to start with
• Document the search process in a text document
• Identify appropriate index terms in the thesaurus of the first database
• Identify synonyms in the thesaurus
• Add variations in search terms
• Use database-appropriate syntax, with parentheses, Boolean operators, and field codes
• Optimize the search
• Evaluate the initial results
• Check for errors
• Translate to other databases
• Test and reiterate

Each step in the process is reflected by an example search described in the supplementary appendix .

1. Determine a clear and focused question

A systematic search can best be applied to a well-defined and precise research or clinical question. Questions that are too broad or too vague cannot be answered easily in a systematic way and will generally result in an overwhelming number of search results. On the other hand, a question that is too specific will result into too few or even zero search results. Various papers describe this process in more detail [ 10 – 12 ].

2. Describe the articles that can answer the question

Although not all clinical or research questions can be answered in the literature, the next step is to presume that the answer can indeed be found in published studies. A good starting point for a search is hypothesizing what the research that can answer the question would look like. These hypothetical (when possible, combined with known) articles can be used as guidance for constructing the search strategy.

3. Decide which key concepts address the different elements of the question

Key concepts are the topics or components that the desired articles should address, such as diseases or conditions, actions, substances, settings, domains (e.g., therapy, diagnosis, etiology), or study types. Key concepts from the research question can be grouped to create elements in the search strategy.

Elements in a search strategy do not necessarily follow the patient, intervention, comparison, outcome (PICO) structure or any other related structure. Using the PICO or another similar framework as guidance can be helpful to consider, especially in the inclusion and exclusion review stage of the SR, but this is not necessary for good search strategy development [ 13 – 15 ]. Sometimes concepts from different parts of the PICO structure can be grouped together into one search element, such as when the desired outcome is frequently described in a certain study type.

4. Decide which elements should be used for the best results

Not all elements of a research question should necessarily be used in the search strategy. Some elements are less important than others or may unnecessarily complicate or restrict a search strategy. Adding an element to a search strategy increases the chance of missing relevant references. Therefore, the number of elements in a search strategy should remain as low as possible to optimize recall.

Using the schema in Figure 1 , elements can be ordered by their specificity and importance to determine the best search approach. Whether an element is more specific or more general can be measured objectively by the number of hits retrieved in a database when searching for a key term representing that element. Depending on the research question, certain elements are more important than others. If articles (hypothetically or known) exist that can answer the question but lack a certain element in their titles, abstracts, or keywords, that element is unimportant to the question. An element can also be unimportant because of expected bias or an overlap with another element.

Schema for determining the optimal order of elements

Bias in elements

The choice of elements in a search strategy can introduce bias through use of overly specific terminology or terms often associated with positive outcomes. For the question “does prolonged breastfeeding improve intelligence outcomes in children?,” searching specifically for the element of duration will introduce bias, as articles that find a positive effect of prolonged breastfeeding will be much more likely to mention time factors in their titles or abstracts.

Overlapping elements

Elements in a question sometimes overlap in their meaning. Sometimes certain therapies are interventions for one specific disease. The Lichtenstein technique, for example, is a repair method for inguinal hernias. There is no need to include an element of “inguinal hernias” to a search for the effectiveness of the Lichtenstein therapy. Likewise, sometimes certain diseases are only found in certain populations. Adding such an overlapping element could lead to missing relevant references.

The elements to use in a search strategy can be found in the plot of elements in Figure 1 , by following the top row from left to right. For this method, we recommend starting with the most important and specific elements. Then, continue with more general and important elements until the number of results is acceptable for screening. Determining how many results are acceptable for screening is often a matter of negotiation with the SR team.

5. Choose an appropriate database and interface to start with

Important factors for choosing databases to use are the coverage and the presence of a thesaurus. For medically oriented searches, the coverage and recall of Embase, which includes the MEDLINE database, are superior to those of MEDLINE [ 16 ]. Each of these two databases has its own thesaurus with its own unique definitions and structure. Because of the complexity of the Embase thesaurus, Emtree, which contains much more specific thesaurus terms than the MEDLINE Medical Subject Headings (MeSH) thesaurus, translation from Emtree to MeSH is easier than the other way around. Therefore, we recommend starting in Embase.

MEDLINE and Embase are available through many different vendors and interfaces. The choice of an interface and primary database is often determined by the searcher’s accessibility. For our method, an interface that allows searching with proximity operators is desirable, and full functionality of the thesaurus, including explosion of narrower terms, is crucial. We recommend developing a personal workflow that always starts with one specific database and interface.

6. Document the search process in a text document

We advise designing and creating the complete search strategies in a log document, instead of directly in the database itself, to register the steps taken and to make searches accountable and reproducible. The developed search strategies can be copied and pasted into the desired databases from the log document. This way, the searcher is in control of the whole process. Any change to the search strategy should be done in the log document, assuring that the search strategy in the log is always the most recent.

7. Identify appropriate index terms in the thesaurus of the first database

Searches should start by identifying appropriate thesaurus terms for the desired elements. The thesaurus of the database is searched for matching index terms for each key concept. We advise restricting the initial terms to the most important and most relevant terms. Later in the process, more general terms can be added in the optimization process, in which the effect on the number of hits, and thus the desirability of adding these terms, can be evaluated more easily.

Several factors can complicate the identification of thesaurus terms. Sometimes, one thesaurus term is found that exactly describes a specific element. In contrast, especially in more general elements, multiple thesaurus terms can be found to describe one element. If no relevant thesaurus terms have been found for an element, free-text terms can be used, and possible thesaurus terms found in the resulting references can be added later (step 11).

Sometimes, no distinct thesaurus term is available for a specific key concept that describes the concept in enough detail. In Emtree, one thesaurus term often combines two or more elements. The easiest solution for combining these terms for a sensitive search is to use such a thesaurus term in all elements where it is relevant. Examples are given in the supplementary appendix .

8. Identify synonyms in the thesaurus

Most thesauri offer a list of synonyms on their term details page (named Synonyms in Emtree and Entry Terms in MeSH). To create a sensitive search strategy for SRs, these terms need to be searched as free-text keywords in the title and abstract fields, in addition to searching their associated thesaurus terms.

The Emtree thesaurus contains more synonyms (300,000) than MeSH does (220,000) [ 17 ]. The difference in number of terms is even higher considering that many synonyms in MeSH are permuted terms (i.e., inversions of phrases using commas).

Thesaurus terms are ordered in a tree structure. When searching for a more general thesaurus term, the more specific (narrower) terms in the branches below that term will also be searched (this is frequently referred to as “exploding” a thesaurus term). However, to perform a sensitive search, all relevant variations of the narrower terms must be searched as free-text keywords in the title or abstract, in addition to relying on the exploded thesaurus term. Thus, all articles that describe a certain narrower topic in their titles and abstracts will already be retrieved before MeSH terms are added.

9. Add variations in search terms (e.g., truncation, spelling differences, abbreviations, opposites)

Truncation allows a searcher to search for words beginning with the same word stem. A search for therap* will, thus, retrieve therapy, therapies, therapeutic, and all other words starting with “therap.” Do not truncate a word stem that is too short. Also, limitations of interfaces should be taken into account, especially in PubMed, where the number of search term variations that can be found by truncation is limited to 600.

Databases contain references to articles using both standard British and American English spellings. Both need to be searched as free-text terms in the title and abstract. Alternatively, many interfaces offer a certain code to replace zero or one characters, allowing a search for “pediatric” or “paediatric” as “p?ediatric.” Table 1 provides a detailed description of the syntax for different interfaces.

Field codes in five most used interfaces for biomedical literature searching

Searching for abbreviations can identify extra, relevant references and retrieve more irrelevant ones. The search can be more focused by combining the abbreviation with an important word that is relevant to its meaning or by using the Boolean “NOT” to exclude frequently observed, clearly irrelevant results. We advise that searchers do not exclude all possible irrelevant meanings, as it is very time consuming to identify all the variations, it will result in unnecessarily complicated search strategies, and it may lead to erroneously narrowing the search and, thereby, reduce recall.

Searching partial abbreviations can be useful for retrieving relevant references. For example, it is very likely that an article would mention osteoarthritis (OA) early in the abstract, replacing all further occurrences of osteoarthritis with OA . Therefore, it may not contain the phrase “hip osteoarthritis” but only “hip oa.”

It is also important to search for the opposites of search terms to avoid bias. When searching for “disease recurrence,” articles about “disease free” may be relevant as well. When the desired outcome is survival , articles about mortality may be relevant.

10. Use database-appropriate syntax, with parentheses, Boolean operators, and field codes

Different interfaces require different syntaxes, the special set of rules and symbols unique to each database that define how a correctly constructed search operates. Common syntax components include the use of parentheses and Boolean operators such as “AND,” “OR,” and “NOT,” which are available in all major interfaces. An overview of different syntaxes for four major interfaces for bibliographic medical databases (PubMed, Ovid, EBSCOhost, Embase.com, and ProQuest) is shown in Table 1 .

Creating the appropriate syntax for each database, in combination with the selected terms as described in steps 7–9, can be challenging. Following the method outlined below simplifies the process:

• Create single-line queries in a text document (not combining multiple record sets), which allows immediate checking of the relevance of retrieved references and efficient optimization.
• Type the syntax (Boolean operators, parentheses, and field codes) before adding terms, which reduces the chance that errors are made in the syntax, especially in the number of parentheses.
• Use predefined proximity structures including parentheses, such as (() ADJ3 ()) in Ovid, that can be reused in the query when necessary.
• Use thesaurus terms separately from free-text terms of each element. Start an element with all thesaurus terms (using “OR”) and follow with the free-text terms. This allows the unique optimization methods as described in step 11.
• When adding terms to an existing search strategy, pay close attention to the position of the cursor. Make sure to place it appropriately either in the thesaurus terms section, in the title/abstract section, or as an addition (broadening) to an existing proximity search.

The supplementary appendix explains the method of building a query in more detail, step by step for different interfaces: PubMed, Ovid, EBSCOhost, Embase.com, and ProQuest. This method results in a basic search strategy designed to retrieve some relevant references upon which a more thorough search strategy can be built with optimization such as described in step 11.

11. Optimize the search

The most important question when performing a systematic search is whether all (or most) potentially relevant articles have been retrieved by the search strategy. This is also the most difficult question to answer, since it is unknown which and how many articles are relevant. It is, therefore, wise first to broaden the initial search strategy, making the search more sensitive, and then check if new relevant articles are found by comparing the set results (i.e., search for Strategy #2 NOT Strategy #1 to see the unique results).

A search strategy should be tested for completeness. Therefore, it is necessary to identify extra, possibly relevant search terms and add them to the test search in an OR relationship with the already used search terms. A good place to start, and a well-known strategy, is scanning the top retrieved articles when sorted by relevance, looking for additional relevant synonyms that could be added to the search strategy.

We have developed a unique optimization method that has not been described before in the literature. This method often adds valuable extra terms to our search strategy and, therefore, extra, relevant references to our search results. Extra synonyms can be found in articles that have been assigned a certain set of thesaurus terms but that lack synonyms in the title and/or abstract that are already present in the current search strategy. Searching for thesaurus terms NOT free-text terms will help identify missed free-text terms in the title or abstract. Searching for free-text terms NOT thesaurus terms will help identify missed thesaurus terms. If this is done repeatedly for each element, leaving the rest of the query unchanged, this method will help add numerous relevant terms to the query. These steps are explained in detail for five different search platforms in the supplementary appendix .

12. Evaluate the initial results

The results should now contain relevant references. If the interface allows relevance ranking, use that in the evaluation. If you know some relevant references that should be included in the research, search for those references specifically; for example, combine a specific (first) author name with a page number and the publication year. Check whether those references are retrieved by the search. If the known relevant references are not retrieved by the search, adapt the search so that they are. If it is unclear which element should be adapted to retrieve a certain article, combine that article with each element separately.

Different outcomes are desired for different types of research questions. For instance, in the case of clinical question answering, the researcher will not be satisfied with many references that contain a lot of irrelevant references. A clinical search should be rather specific and is allowed to miss a relevant reference. In the case of an SR, the researchers do not want to miss any relevant reference and are willing to handle many irrelevant references to do so. The search for references to include in an SR should be very sensitive: no included reference should be missed. A search that is too specific or too sensitive for the intended goal can be adapted to become more sensitive or specific. Steps to increase sensitivity or specificity of a search strategy can be found in the supplementary appendix .

13. Check for errors

Errors might not be easily detected. Sometimes clues can be found in the number of results, either when the number of results is much higher or lower than expected or when many retrieved references are not relevant. However, the number expected is often unknown, and very sensitive search strategies will always retrieve many irrelevant articles. Each query should, therefore, be checked for errors.

One of the most frequently occurring errors is missing the Boolean operator “OR.” When no “OR” is added between two search terms, many interfaces automatically add an “AND,” which unintentionally reduces the number of results and likely misses relevant references. One good strategy to identify missing “OR”s is to go to the web page containing the full search strategy, as translated by the database, and using Ctrl-F search for “AND.” Check whether the occurrences of the “AND” operator are deliberate.

Ideally, search strategies should be checked by other information specialists [ 18 ]. The Peer Review of Electronic Search Strategies (PRESS) checklist offers good guidance for this process [ 4 ]. Apart from the syntax (especially Boolean operators and field codes) of the search strategy, it is wise to have the search terms checked by the clinician or researcher familiar with the topic. At Erasmus MC, researchers and clinicians are involved during the complete process of structuring and optimizing the search strategy. Each word is added after the combined decision of the searcher and the researcher, with the possibility of directly comparing results with and without the new term.

14. Translate to other databases

To retrieve as many relevant references as possible, one has to search multiple databases. Translation of complex and exhaustive queries between different databases can be very time consuming and cumbersome. The single-line search strategy approach detailed above allows quick translations using the find and replace method in Microsoft Word (<Ctrl-H>).

At Erasmus MC, macros based on the find-and-replace method in Microsoft Word have been developed for easy and fast translation between the most used databases for biomedical and health sciences questions. The schema that is followed for the translation between databases is shown in Figure 2 . Most databases simply follow the structure set by the Embase.com search strategy. The translation from Emtree terms to MeSH terms for MEDLINE in Ovid often identifies new terms that need to be added to the Embase.com search strategy before the translation to other databases.

Schematic representation of translation between databases used at Erasmus University Medical Center

Dotted lines represent databases that are used in less than 80% of the searches.

Using five different macros, a thoroughly optimized query in Embase.com can be relatively quickly translated into eight major databases. Basic search strategies will be created to use in many, mostly smaller, databases, because such niche databases often do not have extensive thesauri or advanced syntax options. Also, there is not much need to use extensive syntax because the number of hits and, therefore, the amount of noise in these databases is generally low. In MEDLINE (Ovid), PsycINFO (Ovid), and CINAHL (EBSCOhost), the thesaurus terms must be adapted manually, as each database has its own custom thesaurus. These macros and instructions for their installation, use, and adaptation are available at bit.ly/databasemacros.

15. Test and reiterate

Ideally, exhaustive search strategies should retrieve all references that are covered in a specific database. For SR search strategies, checking searches for their recall is advised. This can be done after included references have been determined by the authors of the systematic review. If additional papers have been identified through other non-database methods (i.e., checking references in included studies), results that were not identified by the database searches should be examined. If these results were available in the databases but not located by the search strategy, the search strategy should be adapted to try to retrieve these results, as they may contain terms that were omitted in the original search strategies. This may enable the identification of additional relevant results.

A methodology for creating exhaustive search strategies has been created that describes all steps of the search process, starting with a question and resulting in thorough search strategies in multiple databases. Many of the steps described are not new, but together, they form a strong method creating high-quality, robust searches in a relatively short time frame.

Our methodology is intended to create thoroughness for literature searches. The optimization method, as described in step 11, will identify missed synonyms or thesaurus terms, unlike any other method that largely depends on predetermined keywords and synonyms. Using this method results in a much quicker search process, compared to traditional methods, especially because of the easier translation between databases and interfaces (step 13). The method is not a guarantee for speed, since speed depends on many factors, including experience. However, by following the steps and using the tools as described above, searchers can gain confidence first and increase speed through practice.

What is new?

This method encourages searchers to start their search development process using empty syntax first and later adding the thesaurus terms and free-text synonyms. We feel this helps the searcher to focus on the search terms, instead of on the structure of the search query. The optimization method in which new terms are found in the already retrieved articles is used in some other institutes as well but has to our knowledge not been described in the literature. The macros to translate search strategies between interfaces are unique in this method.

What is different compared to common practice?

Traditionally, librarians and information specialists have focused on creating complex, multi-line (also called line-by-line) search strategies, consisting of multiple record sets, and this method is frequently advised in the literature and handbooks [ 2 , 19 – 21 ]. Our method, instead, uses single-line searches, which is critical to its success. Single-line search strategies can be easily adapted by adding or dropping a term without having to recode numbers of record sets, which would be necessary in multi-line searches. They can easily be saved in a text document and repeated by copying and pasting for search updates. Single-line search strategies also allow easy translation to other syntaxes using find-and-replace technology to update field codes and other syntax elements or using macros (step 13).

When constructing a search strategy, the searcher might experience that certain parentheses in the syntax are unnecessary, such as parentheses around all search terms in the title/abstract portion, if there is only one such term, there are double parentheses in the proximity statement, or one of the word groups exists for only one word. One might be tempted to omit those parentheses for ease of reading and management. However, during the optimization process, the searcher is likely to find extra synonyms that might consist of one word. To add those terms to the first query (with reduced parentheses) requires adding extra parentheses (meticulously placing and counting them), whereas, in the latter search, it only requires proper placement of those terms.

Many search methods highly depend on the PICO framework. Research states that often PICO or PICOS is not suitable for every question [ 22 , 23 ]. There are other acronyms than PICO—such as sample, phenomenon of interest, design, evaluation, research type (SPIDER) [ 24 ]—but each is just a variant. In our method, the most important and specific elements of a question are being analyzed for building the best search strategy.

Though it is generally recommended that searchers search both MEDLINE and Embase, most use MEDLINE as the starting point. It is considered the gold standard for biomedical searching, partially due to historical reasons, since it was the first of its kind, and more so now that it is freely available via the PubMed interface. Our method can be used with any database as a starting point, but we use Embase instead of MEDLINE or another database for a number of reasons. First, Embase provides both unique content and the complete content of MEDLINE. Therefore, searching Embase will be, by definition, more complete than searching MEDLINE only. Second, the number of terms in Emtree (the Embase thesaurus) is three times as high as that of MeSH (the MEDLINE thesaurus). It is easier to find MeSH terms after all relevant Emtree terms have been identified than to start with MeSH and translate to Emtree.

At Erasmus MC, the researchers sit next to the information specialist during most of the search strategy design process. This way, the researchers can deliver immediate feedback on the relevance of proposed search terms and retrieved references. The search team then combines knowledge about databases with knowledge about the research topic, which is an important condition to create the highest quality searches.

Limitations of the method

One disadvantage of single-line searches compared to multi-line search strategies is that errors are harder to recognize. However, with the methods for optimization as described (step 11), errors are recognized easily because missed synonyms and spelling errors will be identified during the process. Also problematic is that more parentheses are needed, making it more difficult for the searcher and others to assess the logic of the search strategy. However, as parentheses and field codes are typed before the search terms are added (step 10), errors in parentheses can be prevented.

Our methodology works best if used in an interface that allows proximity searching. It is recommended that searchers with access to an interface with proximity searching capabilities select one of those as the initial database to develop and optimize the search strategy. Because the PubMed interface does not allow proximity searches, phrases or Boolean “AND” combinations are required. Phrase searching complicates the process and is more specific, with the higher risk of missing relevant articles, and using Boolean “AND” combinations increases sensitivity but at an often high loss of specificity. Due to some searchers’ lack of access to expensive databases or interfaces, the freely available PubMed interface may be necessary to use, though it should never be the sole database used for an SR [ 2 , 16 , 25 ]. A limitation of our method is that it works best with subscription-based and licensed resources.

Another limitation is the customization of the macros to a specific institution’s resources. The macros for the translation between different database interfaces only work between the interfaces as described. To mitigate this, we recommend using the find-and-replace functionality of text editors like Microsoft Word to ease the translation of syntaxes between other databases. Depending on one’s institutional resources, custom macros can be developed using similar methods.

Results of the method

Whether this method results in exhaustive searches where no important article is missed is difficult to determine, because the number of relevant articles is unknown for any topic. A comparison of several parameters of 73 published reviews that were based on a search developed with this method to 258 reviews that acknowledged information specialists from other Dutch academic hospitals shows that the performance of the searches following our method is comparable to those performed in other institutes but that the time needed to develop the search strategies was much shorter than the time reported for the other reviews [ 9 ].

CONCLUSIONS

With the described method, searchers can gain confidence in their search strategies by finding many relevant words and creating exhaustive search strategies quickly. The approach can be used when performing SR searches or for other purposes such as answering clinical questions, with different expectations of the search’s precision and recall. This method, with practice, provides a stepwise approach that facilitates the search strategy development process from question clarification to final iteration and beyond.

SUPPLEMENTAL FILE

Acknowledgments.

We highly appreciate the work that was done by our former colleague Louis Volkers, who in his twenty years as an information specialist in Erasmus MC laid the basis for our method. We thank Professor Oscar Franco for reviewing earlier drafts of this article.

Best Practice for Literature Searching

• Literature Search Best Practice

What is literature searching?

• What are literature reviews?
• Hierarchies of evidence
• 1. Managing references
• 2. Defining your research question
• 3. Where to search
• 4. Search strategy
• 5. Screening results
• 6. Paper acquisition
• 7. Critical appraisal
• Further resources
• Training opportunities and videos
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Literature searching is the task of finding relevant information on a topic from the available research literature. Literature searches range from short fact-finding missions to comprehensive and lengthy funded systematic reviews. Or, you may want to establish through a literature review that no one has already done the research you are conducting. If so, a comprehensive search is essential to be sure that this is true.

Whatever the scale, the aim of literature searches is to gain knowledge and aid decision-making.  They are embedded in the scientific discovery process. Literature searching is a vital component of what is called "evidence-based practice", where decisions are based on the best available evidence.

What is "literature"?

Research literature writes up research that has been done in order to share it with others around the world. Far more people can read a research article than could ever visit a particular lab, so the article is the vehicle for disseminating the research.  A research article describes in detail the research that's been done, and what the researchers think can be concluded from it.   

It is important, in literature searching, that you search for  research literature .  Scientific information is published in different formats for different purposes: in  textbooks  to teach students; in  opinion  pieces, sometimes called  editorials  or  commentaries , to persuade peers; in  review articles  to survey the state of knowledge.  An abundance of other literature is available online, but not actually published (by an academic publisher)--this includes things like  conference proceedings ,  working papers, reports  and  preprints .  This type of material is called grey (or gray) literature . 

Most of the time what you are looking for for your literature review is research literature (and not opinion pieces, grey literature, or textbook material) that has been published in  scholarly peer reviewed journals .

As expertise builds, using a greater diversity of literature becomes more appropriate.  For instance, advanced students might use conference proceedings in a literature review to map the direction of new and forthcoming research. The most advanced literature reviews, systematic reviews, need to try to track down unpublished studies to be comprehensive, and a great challenge can be locating not only relevant grey literature, but studies that have been conducted but not published anywhere.  If in doubt, always check with a teacher or supervisor about what type of literature you should be including in your search.   

Why undertake literature searches?

By undertaking regular literature searches in your area of expertise, or undertaking complex literature reviews, you are:

• Able to provide context for and justify your research
• Exploring new research methods
• Highlighting gaps in existing research
• Checking if research has been done before
• Showing how your research fits with existing evidence
• Identifying flaws and bias in existing research
• Learning about terminology and different concepts related to your field
• Able to track larger trends
• Understanding what the majority of researchers have found on certain questions.
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• Next: What are literature reviews? >>
• Last Updated: Sep 15, 2023 2:17 PM
• URL: https://ifis.libguides.com/literature_search_best_practice

A systematic approach to searching: an efficient and complete method to develop literature searches

Affiliations.

• 1 Biomedical Information Specialist, Medical Library, Erasmus MC-Erasmus University Medical Centre, Rotterdam, The Netherlands.
• 2 Medical Library, Erasmus MC-Erasmus University Medical Centre, Rotterdam, The Netherlands.
• 3 Spencer S. Eccles Health Sciences Library, University of Utah, Salt Lake City, UT.
• 4 Department of Family Medicine, School for Public Health and Primary Care (CAPHRI), Maastricht University, Maastricht, The Netherlands, and Kleijnen Systematic Reviews, York, United Kingdom.
• PMID: 30271302
• PMCID: PMC6148622
• DOI: 10.5195/jmla.2018.283

Creating search strategies for systematic reviews, finding the best balance between sensitivity and specificity, and translating search strategies between databases is challenging. Several methods describe standards for systematic search strategies, but a consistent approach for creating an exhaustive search strategy has not yet been fully described in enough detail to be fully replicable. The authors have established a method that describes step by step the process of developing a systematic search strategy as needed in the systematic review. This method describes how single-line search strategies can be prepared in a text document by typing search syntax (such as field codes, parentheses, and Boolean operators) before copying and pasting search terms (keywords and free-text synonyms) that are found in the thesaurus. To help ensure term completeness, we developed a novel optimization technique that is mainly based on comparing the results retrieved by thesaurus terms with those retrieved by the free-text search words to identify potentially relevant candidate search terms. Macros in Microsoft Word have been developed to convert syntaxes between databases and interfaces almost automatically. This method helps information specialists in developing librarian-mediated searches for systematic reviews as well as medical and health care practitioners who are searching for evidence to answer clinical questions. The described method can be used to create complex and comprehensive search strategies for different databases and interfaces, such as those that are needed when searching for relevant references for systematic reviews, and will assist both information specialists and practitioners when they are searching the biomedical literature.

• Abstracting and Indexing / standards*
• Databases, Factual / standards*
• Information Storage and Retrieval / methods*
• Medical Subject Headings
• Review Literature as Topic*
• Vocabulary, Controlled

Developing NICE guidelines: the manual

NICE process and methods [PMG20] Published: 31 October 2014 Last updated: 17 January 2024

• Tools and resources
• 1 Introduction
• 2 The scope
• 3 Decision-making committees
• 4 Developing review questions and planning the evidence review

5 Identifying the evidence: literature searching and evidence submission

• 6 Reviewing evidence
• 7 Incorporating economic evaluation
• 8 Linking to other guidance
• 9 Interpreting the evidence and writing the guideline
• 10 The validation process for draft guidelines, and dealing with stakeholder comments
• 11 Finalising and publishing the guideline recommendations
• 12 Support for putting the guideline recommendations into practice
• 13 Ensuring that published guidelines are current and accurate
• 14 Updating guideline recommendations
• 15 Appendices
• Update information

NICE process and methods

5.1 introduction, 5.2 searches during guideline recommendation scoping and surveillance, 5.3 searches during guideline recommendation development, 5.4 health inequalities and equality and diversity, 5.5 quality assurance, 5.6 documenting the search, 5.7 re-running searches, 5.8 calls for evidence from stakeholders, 5.9 references and further reading.

The systematic identification of evidence is an essential step in developing NICE guideline recommendations.

This chapter sets out how evidence is identified at each stage of the guideline development cycle. It provides details of the systematic literature searching methods used to identify the best available evidence for NICE guidelines. It also provides details of associated information management processes including quality assurance (peer review), re‑running searches, and documenting the search process.

Our searching methods are informed by the chapter on searching & selecting studies in the Cochrane Handbook for Systematic Reviews of Interventions and the Campbell Collaboration's searching for studies guide . The Summarized Research in Information Retrieval for HTA (SuRe Info) resource also provides research-based advice on information retrieval for systematic reviews.

Our literature searches are designed to be systematic, transparent, and reproducible, and minimise dissemination bias. Dissemination bias may affect the results of reviews and includes publication bias and database bias.

We use search methods that balance recall and precision. When the need to reduce the number of studies requires pragmatic search approaches that may increase the risk of missing relevant studies, the context and trade-offs are discussed and agreed within the development team and made explicit in the reported search methods.

A flexible approach to identifying evidence is adopted, guided by the subject of the review question (see the chapter on developing review questions and planning the evidence review ), type of evidence sought, and the resource constraints of the evidence review. Often an evidence review will be an update of our earlier work, therefore the approach can be informed by previous searches and surveillance reviews (see the chapter on ensuring that published guidelines are current and accurate ).

Scoping searches

Scoping searches are top-level searches to support scope development. The purpose of the searches is to investigate the current evidence around the topic, and to identify any areas where an evidence review may be beneficial and any research gaps. The results of the searches are used to draft the scope of the upcoming guideline or update and to inform the discussions at scoping workshops (if held). Scoping searches do not aim to be exhaustive.

In some cases, scoping searches are not required when it is more efficient to use the surveillance review (see the chapter on the scope ).

The sources searched at scoping stage will vary according to the topic, type of review questions the guideline or update will seek to address, and type of evidence sought. Each scoping search is tailored using combinations of the following types of information:

NICE guidance and guidance from other organisations

policy and legislation guides

key systematic reviews and epidemiological reviews

economic evaluations

current practice data, including costs and resource use and any safety concerns

views and experiences of people using services, their family members or carers, or the public

other real-world health and social care data (for example audits, surveys, registries, electronic health records, patient-generated health data), if appropriate

summaries of interventions that may be appropriate, including any national safety advice

statistics (for example on epidemiology, natural history of the condition, service configuration or national prevalence data).

All scoping searches are fully documented and if new issues are identified at a scoping workshop, the search is updated. A range of possible sources considered for scoping searches is provided in the appendix on suggested sources for scoping .

Health inequalities searches

The purpose of these searches is to identify evidence to help inform the scope, health inequalities briefing, or the equality and health inequalities assessment (EHIA). They help identify key issues relevant to health inequalities on the topic, for example covering protected characteristics, groups experiencing or at risk of inequalities, or wider determinants of health.

The searches involve finding key data sources, such as routinely available national databases, audits or published reports by charities, non-governmental bodies, or government organisations.

Surveillance searches

Surveillance determines whether published recommendations remain current. The searches are tailored to the evidence required. This may include searches for new or updated policies, legislation, guidance from other organisations, or ongoing studies in the area covered by the evidence review.

If required, published evidence is identified by searching a range of bibliographic databases relevant to the topic. Surveillance searches generally use the same core set of databases used during the development of the original evidence review. A list of sources is given in the appendix on sources for evidence reviews .

The search approach and sources will vary between topics and may include:

population and intervention searches

focused searches for specific question areas

forward and backward citation searching.

Searches usually focus on randomised controlled trials and systematic reviews, although other study types will be considered where appropriate, for example for diagnostic questions.

The search period starts at either the end of the search for the last update of a guideline evidence review, or at the last search date for any previous surveillance check. Where appropriate, living evidence surveillance could be set up to continuously monitor the publication of new evidence over a period of time until impact reaches the threshold for actions. For more information on NICE guideline recommendation surveillance, see the chapter on ensuring that guideline recommendations are current and accurate and appendix on surveillance - interim principles for monitoring approaches of guideline recommendations .

Search protocols

Search protocols form part of the wider guideline review protocol (see the appendix on the review protocol template ). They pre‑define how the evidence is identified and provide a basis for developing the search strategies.

Once the final scope is agreed, the information specialist develops the search protocols and agrees them with the development team before the evidence search begins.

A search protocol includes the following elements:

approach to the search strategy, tailored to the review question and eligibility criteria

sources to be searched

plans to use any additional or alternative search techniques , when known at the protocol development stage, and the reasons for their use

details of any limits to be applied to the search

references to any key papers used to inform the search approach.

Searches are done on a mix of bibliographic databases, websites and other sources, depending on the subject of the review question and the type of evidence sought.

For most searches there are key sources that are prioritised, and other potentially relevant sources that can be considered. It is important to ensure adequate coverage of the relevant literature and to search a range of sources. However, there are practical limits to the number of sources that can be searched in the standard time available for an evidence review.

The selection of sources varies according to the requirements of the review question.

Clinical intervention sources

For reviews of the effectiveness of clinical interventions the following sources are prioritised for searching:

the Cochrane Central Register of Controlled Trials (CENTRAL)

the Cochrane Database of Systematic Reviews (CDSR)

Clinical safety sources

In addition to the sources searched for clinical interventions, the following should be prioritised for clinical safety review questions:

MHRA drug safety updates

National patient safety alerts .

Antimicrobial resistance sources

For reviews of antimicrobial resistance, the following sources should be prioritised:

UK Health Security Agency's English surveillance programme for antimicrobial utilisation and resistance (ESPAUR) report

UK Health Security Agency's antimicrobial resistance local indicators .

Cost-effectiveness sources

For reviews of cost effectiveness, economic databases are used in combination with general bibliographic databases, such as MEDLINE and Embase (see appendix G on sources for economic reviews ).

Economic evaluations of social care interventions may be published in journals that are not identified through standard searches. Targeted searches based on references of key articles and contacting authors can be considered to identify relevant papers.

Topic-specific sources

Some topics we cover may require the use of topic-specific sources. Examples include:

PsycINFO (psychology and psychiatry)

CINAHL (nursing and allied health professions)

ASSIA (Applied Social Sciences Index and Abstracts)

HealthTalk , and other sources to identify the views and experiences of people using services, carers and the public

social policy and practice

social care online

sociological abstracts

transport database

Greenfile (environmental literature)

HMIC (Health Management Information Consortium).

Searching for model inputs

Evidence searches may be needed to inform design-oriented conceptual models. Examples include precise searches to find representative NHS costs for an intervention or finding out the proportion of people offered an intervention who take up the offer.

Some model inputs, such as costs, use national sources such as national list prices or national audit data. In some cases, it may be more appropriate to identify costs from the academic literature. Further advice on methods to identify model inputs are also informed by Paisley (2016) and Kaltenhaler et al. (2011). See also the chapter on incorporating economic evaluation .

Real-world data

Information specialists can identify sources of real-world data (such as electronic health records, registries, and audits) for data analysts to explore further. The Health Data Research Innovation Gateway can be used to identify datasets. The NICE real-world evidence framework (2022) has additional guidance on searching for and selecting real-world data sources.

Grey literature

For some review questions, for example, where significant evidence is likely to be published in non-journal sources and there is a paucity of evidence in published journal sources, it may be appropriate to search for grey literature . Useful sources of grey literature include:

HMIC (Health Management Information Consortium)

TRIP database

Canadian Agency for Drugs and Technology in Health (CADTH) Grey Matters resource .

Committee members may also be able to suggest additional appropriate sources for grey literature.

A list containing potential relevant sources is provided in the appendix on sources for evidence reviews .

Developing search strategies

The approach to devising and structuring search strategies is informed by the review protocol. The PICO (population, intervention, comparator and outcome) or SPICE (setting, perspective, intervention, comparison, evaluation) frameworks may be used to structure a search strategy for intervention review questions. For other types of review questions, alternative frameworks may be more suitable.

It is sometimes more efficient to conduct a single search for multiple review questions, rather than conducting a separate search for each question.

Some topics may not easily lend themselves to PICO- or SPICE-type frameworks. In these cases, it may be better to combine multiple, shorter searches rather than attempting to capture the entire topic using a single search. This is often referred to as multi-stranded searching.

In some instances, for example where the terminology around a topic is diffuse or ill defined, it may be difficult to specify the most appropriate search terms in advance. In these cases, an iterative approach to searching can be used.

In an iterative approach, searching is done in several stages, with each search considering the evidence that has already been retrieved (for example, see Booth et al. 2020 ). Searching in stages allows the reviewers to review the most relevant, high-quality information first and then make decisions for identifying additional evidence if needed.

Decisions to use iterative approaches are agreed by the development team and staff with responsibility for quality assurance because it can affect timelines.

Updating previous work

Where high-quality review-level evidence is available on a topic, the review team may choose to update or expand this previous work rather than duplicating the existing findings. In these cases, the original review searches are re-run and expanded to account for any differences in scope and inclusion criteria between the original review and the update.

Cost-effectiveness searches

There are several methods that can be used to identify economic evaluations:

All relevant review questions can be covered by a single search using the population search terms, combined with a search filter, to identify economic evidence.

The search strategies for individual review questions can be combined with search filters to identify economic evidence. If using this approach, it may be necessary to adapt strategies for some databases to ensure adequate sensitivity.

Economic evidence can be manually sifted while screening evidence from a general literature search (so no separate searches are required).

The rationale for the selected approach is recorded in the search protocol.

Where searches are needed to populate an economic model, these are usually done separately.

Identifying search terms

Search terms usually consist of a combination of subject headings and free‑text terms from the titles and abstracts of relevant references.

When identifying subject headings, variations in thesaurus and indexing terms for each database should be considered, for example MeSH (Medical Subject Headings) in MEDLINE and Emtree in Embase. Not all databases have indexing terms and some contain records that have not yet been indexed.

Free‑text terms may include synonyms, acronyms and abbreviations, spelling variants, old and new terminology, brand and generic medicine names, and lay and medical terminology.

For updates, previous search terms, including those from surveillance searches, are reviewed and used to inform new search terms. New or changed terms are identified, as well as any changes to indexing terms. This also applies when an existing review, for example a Cochrane review, is being updated to answer a review question.

Key studies can be a useful source of search terms, as can reports, guidelines, topic-specific websites, committee members and topic experts.

Some websites and databases have limited search functionality. It may be necessary to use fewer search terms or do multiple searches of the same resource with different search term combinations.

It may be helpful to use frequency analysis or text mining to develop the search-term strategy. Tools such as PubReMiner and Medline Ranker can help, either by highlighting search terms that might not otherwise be apparent, or by flagging terms of high value when exhaustive synonym searching is unfeasible or inadvisable.

Search limits

The application of limits to search strategies will reflect the eligibility criteria in the review protocol. Typically, English language limits, date limits, and the exclusion of conference abstracts and animal studies are usually done as a matter of routine.

Search filters

A search filter is a string of search terms with known (validated) performance. When a particular study design is required for a review question, relevant search filters are usually applied to literature search strategies.

Other search filters relating to age, setting, geography, and health inequalities are also applied as relevant. The most comprehensive list of available search filters is the search filter resource of the InterTASC Information Specialists' SubGroup . This resource also includes critical appraisal tools, which are used for filter selection.

Economics-related filters

A variety of search filters of relevance to cost effectiveness are available. These include filters for economic evaluations, quality of life data, and cost-utilities data. It may be necessary to use more than 1 filter to identify relevant data. In addition, it may be appropriate to add geographic search filters, such as those for the UK or Organisation for Economic Co-operation and Development (OECD) countries, to retrieve economic studies relevant to the UK or OECD (Ayiku et al. 2017, 2019, 2021).

Use of machine learning-based classifiers

Machine learning-based classification software has been developed for some study types (for example the Cochrane RCT classifier, Thomas et al. 2020 ). These classifiers apply a probability weighting to each bibliographical reference within a set of search results. The weighting relates to the reference's likelihood to be a particular study type, based on a model created from analysis of known, relevant papers. The weightings can then be used to either order references for screening or be used with a fixed cut-off value to divide a list of references into those more likely to be included, and those that can be excluded without manual screening.

We support the use of machine classifiers if their performance characteristics are known, and if they improve efficiency in the search and screening process. However, caution is needed when using classifiers, because they may not be as effective if used on data that is different to the type of data for which they were originally developed. For example, the Cochrane RCT classifier is reported to have over 99% recall for health studies but showed "unacceptably low" recall for educational research ( Stansfield et al. 2022 ).

Priority screening, a type of machine classifier that orders references for manual sifting based on previous sifting decisions, is considered in the chapter on reviewing evidence .

Additional search techniques

Additional search techniques are used alongside database searching when it is known, or reasonably likely, that relevant evidence is not indexed in bibliographic databases, or when it will be difficult to retrieve relevant evidence from databases in a way that adequately balances recall and precision. Additional search techniques include forward and backward citation searching, journal hand-searches and contacting experts and stakeholders.

Existing reviews may provide an additional source of primary studies, with reference lists being used as an indirect method of identifying primary research.

Various tools, including Citationchaser and Web of Science, are available to speed up the process of citation searching. These may not be as comprehensive as manual reference list checking (due to limitations of the underlying data sources), but the trade-off in terms of speed is generally acceptable.

All search techniques should follow the same principles of transparency, rigour and reproducibility as other search methods.

If possible, additional search techniques should be considered at the outset and documented in the search protocol. They should also be documented in the supporting appendices for the final evidence review.

All searches aim to be inclusive. This may mean not specifying any population groups.

Searches should avoid inadvertently excluding relevant groups. For example, if the population group is older people, a search for older people should pick up subpopulations such as disabled older people.

Additional search strategies may be needed to target evidence about people with protected characteristics or people experiencing or at risk from other inequalities.

Searches may need to be developed iteratively to ensure coverage of the health inequalities issues or evidence on the impacts of an intervention on equality.

Appropriate terminology for the search should be used, considering how language has evolved.

Quality assuring the literature search is an important step in developing guideline recommendations. Studies have shown that errors do occur.

For each search (including economic searches), the initial MEDLINE search strategy is quality assured by a second information specialist. A standardised checklist, based on the PRESS peer review of electronic search strategies: 2015 guideline statement , is used to ensure clarity and consistency when quality assuring search strategies.

The information specialist carrying out the quality assurance process also considers how appropriate the overall search approach is to the parameters of the evidence review (for example, the time available to carry out the review). The quality assurance comments are recorded and the information specialist who conducted the search should respond to the comments and revise the search strategy as needed.

Search strategy translations across the remaining databases are also checked by a second information specialist to ensure that the strategies have been adapted appropriately, in accordance with the interfaces and search functionality of the sources used.

Details of the evidence search are included as appendices to the individual evidence reviews. They are published for consultation alongside the draft evidence review and included in the final version.

Records are kept of the searches undertaken during guideline recommendation development for all review questions to ensure that the process for identifying the evidence is transparent and reproducible.

We use the PRISMA-S: an extension to the PRISMA statement for reporting literature searches in systematic reviews to inform search reporting. The search documentation is an audit trail that allows the reader to understand both the technical aspect of what was done (such as which sources were searched; what platform was used and on what date; any deviations from the original search protocol) and the underlying rationale for the search approach where this may not be immediately apparent.

Documenting the search begins with creating the search protocol (see the section on search protocols ). If using an iterative or emergent stepped approach, initial search strategies, key decision points and the reasons for subsequent search steps are clearly documented in the search protocol and final evidence review. When using a proprietary search engine such as Google, whose underlying algorithm adapts to different users, the search is reported in a way that should allow the reader to understand what was done.

Searches undertaken to identify evidence for each review question (including economics searches) may be re-run before consultation or before publication. For example, searches are re‑run if the evidence changes quickly, there is reason to believe that substantial new evidence exists, or the development time is longer than usual.

A decision to re‑run searches is taken by the development team and staff with responsibility for quality assurance.

If undertaken, searches are re‑run at least 6 to 8 weeks before the final committee meeting before consultation.

If evidence is identified after the last cut‑off date for searching but before publication, a judgement on its impact is made by the development team and staff with responsibility for quality assurance. In exceptional circumstances, this evidence can be considered if its impact is judged as potentially substantial.

In some topic areas or for some review questions, staff with responsibility for quality assurance, the development team or the committee may believe that there is relevant evidence in addition to that identified by the searches. In these situations, the development team may invite stakeholders, and possibly also other relevant organisations or individuals with a significant role or interest (see expert witnesses in the section on other attendees at committee meetings in the chapter on decision-making committees ), to submit evidence. A call for evidence is issued directly to registered stakeholders on the NICE website. Examples and details of process are included in the appendix on call for evidence and expert witnesses . Confidential information should be kept to an absolute minimum.

Ayiku L, Levay P, Hudson T et al. (2017) The medline UK filter: development and validation of a geographic search filter to retrieve research about the UK from OVID medline. Health Information and Libraries Journal 34(3): 200–216

Ayiku L, Levay P, Hudson T et al. (2019) The Embase UK filter: validation of a geographic search filter to retrieve research about the UK from OVID Embase. Health Information and Libraries Journal 36(2): 121–133

Ayiku L, Hudson T, Williams C et al. (2021) The NICE OECD countries' geographic search filters: Part 2-validation of the MEDLINE and Embase (Ovid) filters . Journal of the Medical Library Association 109(4): 583–9

Booth A, Briscoe S, Wright JM (2020) The "realist search": a systematic review of current practice and reporting . Research Synthesis Methods 11: 14–35

Canadian Agency for Drugs and Technologies in Health (2019) Grey Matters: a practical tool for searching health-related grey literature [online; accessed 24 July 2023]

Glanville J, Lefebvre C, Wright K (editors) (2008, updated 2017) The InterTASC Information Specialists' Subgroup Search Filters Resource [online; accessed 24 July 2023]

Kaltenthaler E, Tappenden P, Paisley S (2011) NICE DSU Technical support document 13: identifying and reviewing evidence to inform the conceptualisation and population of cost-effectiveness models [online; accessed 24 July 2023]

Kugley S, Wade A, Thomas J et al. (2017) Searching for studies: a guide to information retrieval for Campbell systematic reviews . Oslo: The Campbell Collaboration

Lefebvre C, Glanville J, Briscoe S et al. Chapter 4: Searching for and selecting studies . In: Higgins JPT, Thomas J, Cumpston M et al. (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.2 (updated February 2021). Cochrane, 2021

McGowan J, Sampson M, Salzwedel DM et al. (2016) PRESS Peer Review of Electronic Search Strategies: 2015 guideline statement . Journal of Clinical Epidemiology 75: 40–6

National Institute for Health and Care Excellence (2022) NICE real-world evidence framework [online; accessed 24 July 2023]

Paisley S (2016) Identification of key parameters in decision-analytic models of cost-effectiveness: a description of sources and a recommended minimum search requirement. Pharmacoeconomics 34: 597–8

Rethlefsen M, Kirtley S, Waffenschmidt S et al. (2021) PRISMA-S: an extension to the PRISMA statement for reporting literature searches in systematic reviews . Systematic Reviews 10: 39

Stansfield C, Stokes G, Thoman J (2022) Applying machine classifiers to update searches: analysis from two case studies . Research Synthesis Methods 13: 121–33

Summarized research for Information Retrieval in HTA (SuRe Info) [online; accessed 24 July 2023]

• Open access
• Published: 14 August 2018

Defining the process to literature searching in systematic reviews: a literature review of guidance and supporting studies

• Chris Cooper   ORCID: orcid.org/0000-0003-0864-5607 1 ,
• Andrew Booth 2 ,
• Jo Varley-Campbell 1 ,
• Nicky Britten 3 &
• Ruth Garside 4  

BMC Medical Research Methodology volume  18 , Article number:  85 ( 2018 ) Cite this article

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Systematic literature searching is recognised as a critical component of the systematic review process. It involves a systematic search for studies and aims for a transparent report of study identification, leaving readers clear about what was done to identify studies, and how the findings of the review are situated in the relevant evidence.

Information specialists and review teams appear to work from a shared and tacit model of the literature search process. How this tacit model has developed and evolved is unclear, and it has not been explicitly examined before.

The purpose of this review is to determine if a shared model of the literature searching process can be detected across systematic review guidance documents and, if so, how this process is reported in the guidance and supported by published studies.

A literature review.

Two types of literature were reviewed: guidance and published studies. Nine guidance documents were identified, including: The Cochrane and Campbell Handbooks. Published studies were identified through ‘pearl growing’, citation chasing, a search of PubMed using the systematic review methods filter, and the authors’ topic knowledge.

The relevant sections within each guidance document were then read and re-read, with the aim of determining key methodological stages. Methodological stages were identified and defined. This data was reviewed to identify agreements and areas of unique guidance between guidance documents. Consensus across multiple guidance documents was used to inform selection of ‘key stages’ in the process of literature searching.

Eight key stages were determined relating specifically to literature searching in systematic reviews. They were: who should literature search, aims and purpose of literature searching, preparation, the search strategy, searching databases, supplementary searching, managing references and reporting the search process.

Conclusions

Eight key stages to the process of literature searching in systematic reviews were identified. These key stages are consistently reported in the nine guidance documents, suggesting consensus on the key stages of literature searching, and therefore the process of literature searching as a whole, in systematic reviews. Further research to determine the suitability of using the same process of literature searching for all types of systematic review is indicated.

Peer Review reports

Systematic literature searching is recognised as a critical component of the systematic review process. It involves a systematic search for studies and aims for a transparent report of study identification, leaving review stakeholders clear about what was done to identify studies, and how the findings of the review are situated in the relevant evidence.

Information specialists and review teams appear to work from a shared and tacit model of the literature search process. How this tacit model has developed and evolved is unclear, and it has not been explicitly examined before. This is in contrast to the information science literature, which has developed information processing models as an explicit basis for dialogue and empirical testing. Without an explicit model, research in the process of systematic literature searching will remain immature and potentially uneven, and the development of shared information models will be assumed but never articulated.

One way of developing such a conceptual model is by formally examining the implicit “programme theory” as embodied in key methodological texts. The aim of this review is therefore to determine if a shared model of the literature searching process in systematic reviews can be detected across guidance documents and, if so, how this process is reported and supported.

Identifying guidance

Key texts (henceforth referred to as “guidance”) were identified based upon their accessibility to, and prominence within, United Kingdom systematic reviewing practice. The United Kingdom occupies a prominent position in the science of health information retrieval, as quantified by such objective measures as the authorship of papers, the number of Cochrane groups based in the UK, membership and leadership of groups such as the Cochrane Information Retrieval Methods Group, the HTA-I Information Specialists’ Group and historic association with such centres as the UK Cochrane Centre, the NHS Centre for Reviews and Dissemination, the Centre for Evidence Based Medicine and the National Institute for Clinical Excellence (NICE). Coupled with the linguistic dominance of English within medical and health science and the science of systematic reviews more generally, this offers a justification for a purposive sample that favours UK, European and Australian guidance documents.

Nine guidance documents were identified. These documents provide guidance for different types of reviews, namely: reviews of interventions, reviews of health technologies, reviews of qualitative research studies, reviews of social science topics, and reviews to inform guidance.

Whilst these guidance documents occasionally offer additional guidance on other types of systematic reviews, we have focused on the core and stated aims of these documents as they relate to literature searching. Table  1 sets out: the guidance document, the version audited, their core stated focus, and a bibliographical pointer to the main guidance relating to literature searching.

Once a list of key guidance documents was determined, it was checked by six senior information professionals based in the UK for relevance to current literature searching in systematic reviews.

Identifying supporting studies

In addition to identifying guidance, the authors sought to populate an evidence base of supporting studies (henceforth referred to as “studies”) that contribute to existing search practice. Studies were first identified by the authors from their knowledge on this topic area and, subsequently, through systematic citation chasing key studies (‘pearls’ [ 1 ]) located within each key stage of the search process. These studies are identified in Additional file  1 : Appendix Table 1. Citation chasing was conducted by analysing the bibliography of references for each study (backwards citation chasing) and through Google Scholar (forward citation chasing). A search of PubMed using the systematic review methods filter was undertaken in August 2017 (see Additional file 1 ). The search terms used were: (literature search*[Title/Abstract]) AND sysrev_methods[sb] and 586 results were returned. These results were sifted for relevance to the key stages in Fig.  1 by CC.

The key stages of literature search guidance as identified from nine key texts

Extracting the data

To reveal the implicit process of literature searching within each guidance document, the relevant sections (chapters) on literature searching were read and re-read, with the aim of determining key methodological stages. We defined a key methodological stage as a distinct step in the overall process for which specific guidance is reported, and action is taken, that collectively would result in a completed literature search.

The chapter or section sub-heading for each methodological stage was extracted into a table using the exact language as reported in each guidance document. The lead author (CC) then read and re-read these data, and the paragraphs of the document to which the headings referred, summarising section details. This table was then reviewed, using comparison and contrast to identify agreements and areas of unique guidance. Consensus across multiple guidelines was used to inform selection of ‘key stages’ in the process of literature searching.

Having determined the key stages to literature searching, we then read and re-read the sections relating to literature searching again, extracting specific detail relating to the methodological process of literature searching within each key stage. Again, the guidance was then read and re-read, first on a document-by-document-basis and, secondly, across all the documents above, to identify both commonalities and areas of unique guidance.

Results and discussion

Our findings.

We were able to identify consensus across the guidance on literature searching for systematic reviews suggesting a shared implicit model within the information retrieval community. Whilst the structure of the guidance varies between documents, the same key stages are reported, even where the core focus of each document is different. We were able to identify specific areas of unique guidance, where a document reported guidance not summarised in other documents, together with areas of consensus across guidance.

Unique guidance

Only one document provided guidance on the topic of when to stop searching [ 2 ]. This guidance from 2005 anticipates a topic of increasing importance with the current interest in time-limited (i.e. “rapid”) reviews. Quality assurance (or peer review) of literature searches was only covered in two guidance documents [ 3 , 4 ]. This topic has emerged as increasingly important as indicated by the development of the PRESS instrument [ 5 ]. Text mining was discussed in four guidance documents [ 4 , 6 , 7 , 8 ] where the automation of some manual review work may offer efficiencies in literature searching [ 8 ].

Agreement between guidance: Defining the key stages of literature searching

Where there was agreement on the process, we determined that this constituted a key stage in the process of literature searching to inform systematic reviews.

From the guidance, we determined eight key stages that relate specifically to literature searching in systematic reviews. These are summarised at Fig. 1 . The data extraction table to inform Fig. 1 is reported in Table  2 . Table 2 reports the areas of common agreement and it demonstrates that the language used to describe key stages and processes varies significantly between guidance documents.

For each key stage, we set out the specific guidance, followed by discussion on how this guidance is situated within the wider literature.

Key stage one: Deciding who should undertake the literature search

The guidance.

Eight documents provided guidance on who should undertake literature searching in systematic reviews [ 2 , 4 , 6 , 7 , 8 , 9 , 10 , 11 ]. The guidance affirms that people with relevant expertise of literature searching should ‘ideally’ be included within the review team [ 6 ]. Information specialists (or information scientists), librarians or trial search co-ordinators (TSCs) are indicated as appropriate researchers in six guidance documents [ 2 , 7 , 8 , 9 , 10 , 11 ].

How the guidance corresponds to the published studies

The guidance is consistent with studies that call for the involvement of information specialists and librarians in systematic reviews [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ] and which demonstrate how their training as ‘expert searchers’ and ‘analysers and organisers of data’ can be put to good use [ 13 ] in a variety of roles [ 12 , 16 , 20 , 21 , 24 , 25 , 26 ]. These arguments make sense in the context of the aims and purposes of literature searching in systematic reviews, explored below. The need for ‘thorough’ and ‘replicable’ literature searches was fundamental to the guidance and recurs in key stage two. Studies have found poor reporting, and a lack of replicable literature searches, to be a weakness in systematic reviews [ 17 , 18 , 27 , 28 ] and they argue that involvement of information specialists/ librarians would be associated with better reporting and better quality literature searching. Indeed, Meert et al. [ 29 ] demonstrated that involving a librarian as a co-author to a systematic review correlated with a higher score in the literature searching component of a systematic review [ 29 ]. As ‘new styles’ of rapid and scoping reviews emerge, where decisions on how to search are more iterative and creative, a clear role is made here too [ 30 ].

Knowing where to search for studies was noted as important in the guidance, with no agreement as to the appropriate number of databases to be searched [ 2 , 6 ]. Database (and resource selection more broadly) is acknowledged as a relevant key skill of information specialists and librarians [ 12 , 15 , 16 , 31 ].

Whilst arguments for including information specialists and librarians in the process of systematic review might be considered self-evident, Koffel and Rethlefsen [ 31 ] have questioned if the necessary involvement is actually happening [ 31 ].

Key stage two: Determining the aim and purpose of a literature search

The aim: Five of the nine guidance documents use adjectives such as ‘thorough’, ‘comprehensive’, ‘transparent’ and ‘reproducible’ to define the aim of literature searching [ 6 , 7 , 8 , 9 , 10 ]. Analogous phrases were present in a further three guidance documents, namely: ‘to identify the best available evidence’ [ 4 ] or ‘the aim of the literature search is not to retrieve everything. It is to retrieve everything of relevance’ [ 2 ] or ‘A systematic literature search aims to identify all publications relevant to the particular research question’ [ 3 ]. The Joanna Briggs Institute reviewers’ manual was the only guidance document where a clear statement on the aim of literature searching could not be identified. The purpose of literature searching was defined in three guidance documents, namely to minimise bias in the resultant review [ 6 , 8 , 10 ]. Accordingly, eight of nine documents clearly asserted that thorough and comprehensive literature searches are required as a potential mechanism for minimising bias.

The need for thorough and comprehensive literature searches appears as uniform within the eight guidance documents that describe approaches to literature searching in systematic reviews of effectiveness. Reviews of effectiveness (of intervention or cost), accuracy and prognosis, require thorough and comprehensive literature searches to transparently produce a reliable estimate of intervention effect. The belief that all relevant studies have been ‘comprehensively’ identified, and that this process has been ‘transparently’ reported, increases confidence in the estimate of effect and the conclusions that can be drawn [ 32 ]. The supporting literature exploring the need for comprehensive literature searches focuses almost exclusively on reviews of intervention effectiveness and meta-analysis. Different ‘styles’ of review may have different standards however; the alternative, offered by purposive sampling, has been suggested in the specific context of qualitative evidence syntheses [ 33 ].

What is a comprehensive literature search?

Whilst the guidance calls for thorough and comprehensive literature searches, it lacks clarity on what constitutes a thorough and comprehensive literature search, beyond the implication that all of the literature search methods in Table 2 should be used to identify studies. Egger et al. [ 34 ], in an empirical study evaluating the importance of comprehensive literature searches for trials in systematic reviews, defined a comprehensive search for trials as:

a search not restricted to English language;

where Cochrane CENTRAL or at least two other electronic databases had been searched (such as MEDLINE or EMBASE); and

at least one of the following search methods has been used to identify unpublished trials: searches for (I) conference abstracts, (ii) theses, (iii) trials registers; and (iv) contacts with experts in the field [ 34 ].

Tricco et al. (2008) used a similar threshold of bibliographic database searching AND a supplementary search method in a review when examining the risk of bias in systematic reviews. Their criteria were: one database (limited using the Cochrane Highly Sensitive Search Strategy (HSSS)) and handsearching [ 35 ].

Together with the guidance, this would suggest that comprehensive literature searching requires the use of BOTH bibliographic database searching AND supplementary search methods.

Comprehensiveness in literature searching, in the sense of how much searching should be undertaken, remains unclear. Egger et al. recommend that ‘investigators should consider the type of literature search and degree of comprehension that is appropriate for the review in question, taking into account budget and time constraints’ [ 34 ]. This view tallies with the Cochrane Handbook, which stipulates clearly, that study identification should be undertaken ‘within resource limits’ [ 9 ]. This would suggest that the limitations to comprehension are recognised but it raises questions on how this is decided and reported [ 36 ].

What is the point of comprehensive literature searching?

The purpose of thorough and comprehensive literature searches is to avoid missing key studies and to minimize bias [ 6 , 8 , 10 , 34 , 37 , 38 , 39 ] since a systematic review based only on published (or easily accessible) studies may have an exaggerated effect size [ 35 ]. Felson (1992) sets out potential biases that could affect the estimate of effect in a meta-analysis [ 40 ] and Tricco et al. summarize the evidence concerning bias and confounding in systematic reviews [ 35 ]. Egger et al. point to non-publication of studies, publication bias, language bias and MEDLINE bias, as key biases [ 34 , 35 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ]. Comprehensive searches are not the sole factor to mitigate these biases but their contribution is thought to be significant [ 2 , 32 , 34 ]. Fehrmann (2011) suggests that ‘the search process being described in detail’ and that, where standard comprehensive search techniques have been applied, increases confidence in the search results [ 32 ].

Does comprehensive literature searching work?

Egger et al., and other study authors, have demonstrated a change in the estimate of intervention effectiveness where relevant studies were excluded from meta-analysis [ 34 , 47 ]. This would suggest that missing studies in literature searching alters the reliability of effectiveness estimates. This is an argument for comprehensive literature searching. Conversely, Egger et al. found that ‘comprehensive’ searches still missed studies and that comprehensive searches could, in fact, introduce bias into a review rather than preventing it, through the identification of low quality studies then being included in the meta-analysis [ 34 ]. Studies query if identifying and including low quality or grey literature studies changes the estimate of effect [ 43 , 48 ] and question if time is better invested updating systematic reviews rather than searching for unpublished studies [ 49 ], or mapping studies for review as opposed to aiming for high sensitivity in literature searching [ 50 ].

Aim and purpose beyond reviews of effectiveness

The need for comprehensive literature searches is less certain in reviews of qualitative studies, and for reviews where a comprehensive identification of studies is difficult to achieve (for example, in Public health) [ 33 , 51 , 52 , 53 , 54 , 55 ]. Literature searching for qualitative studies, and in public health topics, typically generates a greater number of studies to sift than in reviews of effectiveness [ 39 ] and demonstrating the ‘value’ of studies identified or missed is harder [ 56 ], since the study data do not typically support meta-analysis. Nussbaumer-Streit et al. (2016) have registered a review protocol to assess whether abbreviated literature searches (as opposed to comprehensive literature searches) has an impact on conclusions across multiple bodies of evidence, not only on effect estimates [ 57 ] which may develop this understanding. It may be that decision makers and users of systematic reviews are willing to trade the certainty from a comprehensive literature search and systematic review in exchange for different approaches to evidence synthesis [ 58 ], and that comprehensive literature searches are not necessarily a marker of literature search quality, as previously thought [ 36 ]. Different approaches to literature searching [ 37 , 38 , 59 , 60 , 61 , 62 ] and developing the concept of when to stop searching are important areas for further study [ 36 , 59 ].

The study by Nussbaumer-Streit et al. has been published since the submission of this literature review [ 63 ]. Nussbaumer-Streit et al. (2018) conclude that abbreviated literature searches are viable options for rapid evidence syntheses, if decision-makers are willing to trade the certainty from a comprehensive literature search and systematic review, but that decision-making which demands detailed scrutiny should still be based on comprehensive literature searches [ 63 ].

Key stage three: Preparing for the literature search

Six documents provided guidance on preparing for a literature search [ 2 , 3 , 6 , 7 , 9 , 10 ]. The Cochrane Handbook clearly stated that Cochrane authors (i.e. researchers) should seek advice from a trial search co-ordinator (i.e. a person with specific skills in literature searching) ‘before’ starting a literature search [ 9 ].

Two key tasks were perceptible in preparing for a literature searching [ 2 , 6 , 7 , 10 , 11 ]. First, to determine if there are any existing or on-going reviews, or if a new review is justified [ 6 , 11 ]; and, secondly, to develop an initial literature search strategy to estimate the volume of relevant literature (and quality of a small sample of relevant studies [ 10 ]) and indicate the resources required for literature searching and the review of the studies that follows [ 7 , 10 ].

Three documents summarised guidance on where to search to determine if a new review was justified [ 2 , 6 , 11 ]. These focused on searching databases of systematic reviews (The Cochrane Database of Systematic Reviews (CDSR) and the Database of Abstracts of Reviews of Effects (DARE)), institutional registries (including PROSPERO), and MEDLINE [ 6 , 11 ]. It is worth noting, however, that as of 2015, DARE (and NHS EEDs) are no longer being updated and so the relevance of this (these) resource(s) will diminish over-time [ 64 ]. One guidance document, ‘Systematic reviews in the Social Sciences’, noted, however, that databases are not the only source of information and unpublished reports, conference proceeding and grey literature may also be required, depending on the nature of the review question [ 2 ].

Two documents reported clearly that this preparation (or ‘scoping’) exercise should be undertaken before the actual search strategy is developed [ 7 , 10 ]).

The guidance offers the best available source on preparing the literature search with the published studies not typically reporting how their scoping informed the development of their search strategies nor how their search approaches were developed. Text mining has been proposed as a technique to develop search strategies in the scoping stages of a review although this work is still exploratory [ 65 ]. ‘Clustering documents’ and word frequency analysis have also been tested to identify search terms and studies for review [ 66 , 67 ]. Preparing for literature searches and scoping constitutes an area for future research.

Key stage four: Designing the search strategy

The Population, Intervention, Comparator, Outcome (PICO) structure was the commonly reported structure promoted to design a literature search strategy. Five documents suggested that the eligibility criteria or review question will determine which concepts of PICO will be populated to develop the search strategy [ 1 , 4 , 7 , 8 , 9 ]. The NICE handbook promoted multiple structures, namely PICO, SPICE (Setting, Perspective, Intervention, Comparison, Evaluation) and multi-stranded approaches [ 4 ].

With the exclusion of The Joanna Briggs Institute reviewers’ manual, the guidance offered detail on selecting key search terms, synonyms, Boolean language, selecting database indexing terms and combining search terms. The CEE handbook suggested that ‘search terms may be compiled with the help of the commissioning organisation and stakeholders’ [ 10 ].

The use of limits, such as language or date limits, were discussed in all documents [ 2 , 3 , 4 , 6 , 7 , 8 , 9 , 10 , 11 ].

Search strategy structure

The guidance typically relates to reviews of intervention effectiveness so PICO – with its focus on intervention and comparator - is the dominant model used to structure literature search strategies [ 68 ]. PICOs – where the S denotes study design - is also commonly used in effectiveness reviews [ 6 , 68 ]. As the NICE handbook notes, alternative models to structure literature search strategies have been developed and tested. Booth provides an overview on formulating questions for evidence based practice [ 69 ] and has developed a number of alternatives to the PICO structure, namely: BeHEMoTh (Behaviour of interest; Health context; Exclusions; Models or Theories) for use when systematically identifying theory [ 55 ]; SPICE (Setting, Perspective, Intervention, Comparison, Evaluation) for identification of social science and evaluation studies [ 69 ] and, working with Cooke and colleagues, SPIDER (Sample, Phenomenon of Interest, Design, Evaluation, Research type) [ 70 ]. SPIDER has been compared to PICO and PICOs in a study by Methley et al. [ 68 ].

The NICE handbook also suggests the use of multi-stranded approaches to developing literature search strategies [ 4 ]. Glanville developed this idea in a study by Whitting et al. [ 71 ] and a worked example of this approach is included in the development of a search filter by Cooper et al. [ 72 ].

Writing search strategies: Conceptual and objective approaches

Hausner et al. [ 73 ] provide guidance on writing literature search strategies, delineating between conceptually and objectively derived approaches. The conceptual approach, advocated by and explained in the guidance documents, relies on the expertise of the literature searcher to identify key search terms and then develop key terms to include synonyms and controlled syntax. Hausner and colleagues set out the objective approach [ 73 ] and describe what may be done to validate it [ 74 ].

The use of limits

The guidance documents offer direction on the use of limits within a literature search. Limits can be used to focus literature searching to specific study designs or by other markers (such as by date) which limits the number of studies returned by a literature search. The use of limits should be described and the implications explored [ 34 ] since limiting literature searching can introduce bias (explored above). Craven et al. have suggested the use of a supporting narrative to explain decisions made in the process of developing literature searches and this advice would usefully capture decisions on the use of search limits [ 75 ].

Key stage five: Determining the process of literature searching and deciding where to search (bibliographic database searching)

Table 2 summarises the process of literature searching as reported in each guidance document. Searching bibliographic databases was consistently reported as the ‘first step’ to literature searching in all nine guidance documents.

Three documents reported specific guidance on where to search, in each case specific to the type of review their guidance informed, and as a minimum requirement [ 4 , 9 , 11 ]. Seven of the key guidance documents suggest that the selection of bibliographic databases depends on the topic of review [ 2 , 3 , 4 , 6 , 7 , 8 , 10 ], with two documents noting the absence of an agreed standard on what constitutes an acceptable number of databases searched [ 2 , 6 ].

The guidance documents summarise ‘how to’ search bibliographic databases in detail and this guidance is further contextualised above in terms of developing the search strategy. The documents provide guidance of selecting bibliographic databases, in some cases stating acceptable minima (i.e. The Cochrane Handbook states Cochrane CENTRAL, MEDLINE and EMBASE), and in other cases simply listing bibliographic database available to search. Studies have explored the value in searching specific bibliographic databases, with Wright et al. (2015) noting the contribution of CINAHL in identifying qualitative studies [ 76 ], Beckles et al. (2013) questioning the contribution of CINAHL to identifying clinical studies for guideline development [ 77 ], and Cooper et al. (2015) exploring the role of UK-focused bibliographic databases to identify UK-relevant studies [ 78 ]. The host of the database (e.g. OVID or ProQuest) has been shown to alter the search returns offered. Younger and Boddy [ 79 ] report differing search returns from the same database (AMED) but where the ‘host’ was different [ 79 ].

The average number of bibliographic database searched in systematic reviews has risen in the period 1994–2014 (from 1 to 4) [ 80 ] but there remains (as attested to by the guidance) no consensus on what constitutes an acceptable number of databases searched [ 48 ]. This is perhaps because thinking about the number of databases searched is the wrong question, researchers should be focused on which databases were searched and why, and which databases were not searched and why. The discussion should re-orientate to the differential value of sources but researchers need to think about how to report this in studies to allow findings to be generalised. Bethel (2017) has proposed ‘search summaries’, completed by the literature searcher, to record where included studies were identified, whether from database (and which databases specifically) or supplementary search methods [ 81 ]. Search summaries document both yield and accuracy of searches, which could prospectively inform resource use and decisions to search or not to search specific databases in topic areas. The prospective use of such data presupposes, however, that past searches are a potential predictor of future search performance (i.e. that each topic is to be considered representative and not unique). In offering a body of practice, this data would be of greater practicable use than current studies which are considered as little more than individual case studies [ 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 ].

When to database search is another question posed in the literature. Beyer et al. [ 91 ] report that databases can be prioritised for literature searching which, whilst not addressing the question of which databases to search, may at least bring clarity as to which databases to search first [ 91 ]. Paradoxically, this links to studies that suggest PubMed should be searched in addition to MEDLINE (OVID interface) since this improves the currency of systematic reviews [ 92 , 93 ]. Cooper et al. (2017) have tested the idea of database searching not as a primary search method (as suggested in the guidance) but as a supplementary search method in order to manage the volume of studies identified for an environmental effectiveness systematic review. Their case study compared the effectiveness of database searching versus a protocol using supplementary search methods and found that the latter identified more relevant studies for review than searching bibliographic databases [ 94 ].

Key stage six: Determining the process of literature searching and deciding where to search (supplementary search methods)

Table 2 also summaries the process of literature searching which follows bibliographic database searching. As Table 2 sets out, guidance that supplementary literature search methods should be used in systematic reviews recurs across documents, but the order in which these methods are used, and the extent to which they are used, varies. We noted inconsistency in the labelling of supplementary search methods between guidance documents.

Rather than focus on the guidance on how to use the methods (which has been summarised in a recent review [ 95 ]), we focus on the aim or purpose of supplementary search methods.

The Cochrane Handbook reported that ‘efforts’ to identify unpublished studies should be made [ 9 ]. Four guidance documents [ 2 , 3 , 6 , 9 ] acknowledged that searching beyond bibliographic databases was necessary since ‘databases are not the only source of literature’ [ 2 ]. Only one document reported any guidance on determining when to use supplementary methods. The IQWiG handbook reported that the use of handsearching (in their example) could be determined on a ‘case-by-case basis’ which implies that the use of these methods is optional rather than mandatory. This is in contrast to the guidance (above) on bibliographic database searching.

The issue for supplementary search methods is similar in many ways to the issue of searching bibliographic databases: demonstrating value. The purpose and contribution of supplementary search methods in systematic reviews is increasingly acknowledged [ 37 , 61 , 62 , 96 , 97 , 98 , 99 , 100 , 101 ] but understanding the value of the search methods to identify studies and data is unclear. In a recently published review, Cooper et al. (2017) reviewed the literature on supplementary search methods looking to determine the advantages, disadvantages and resource implications of using supplementary search methods [ 95 ]. This review also summarises the key guidance and empirical studies and seeks to address the question on when to use these search methods and when not to [ 95 ]. The guidance is limited in this regard and, as Table 2 demonstrates, offers conflicting advice on the order of searching, and the extent to which these search methods should be used in systematic reviews.

Key stage seven: Managing the references

Five of the documents provided guidance on managing references, for example downloading, de-duplicating and managing the output of literature searches [ 2 , 4 , 6 , 8 , 10 ]. This guidance typically itemised available bibliographic management tools rather than offering guidance on how to use them specifically [ 2 , 4 , 6 , 8 ]. The CEE handbook provided guidance on importing data where no direct export option is available (e.g. web-searching) [ 10 ].

The literature on using bibliographic management tools is not large relative to the number of ‘how to’ videos on platforms such as YouTube (see for example [ 102 ]). These YouTube videos confirm the overall lack of ‘how to’ guidance identified in this study and offer useful instruction on managing references. Bramer et al. set out methods for de-duplicating data and reviewing references in Endnote [ 103 , 104 ] and Gall tests the direct search function within Endnote to access databases such as PubMed, finding a number of limitations [ 105 ]. Coar et al. and Ahmed et al. consider the role of the free-source tool, Zotero [ 106 , 107 ]. Managing references is a key administrative function in the process of review particularly for documenting searches in PRISMA guidance.

Key stage eight: Documenting the search

The Cochrane Handbook was the only guidance document to recommend a specific reporting guideline: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [ 9 ]. Six documents provided guidance on reporting the process of literature searching with specific criteria to report [ 3 , 4 , 6 , 8 , 9 , 10 ]. There was consensus on reporting: the databases searched (and the host searched by), the search strategies used, and any use of limits (e.g. date, language, search filters (The CRD handbook called for these limits to be justified [ 6 ])). Three guidance documents reported that the number of studies identified should be recorded [ 3 , 6 , 10 ]. The number of duplicates identified [ 10 ], the screening decisions [ 3 ], a comprehensive list of grey literature sources searched (and full detail for other supplementary search methods) [ 8 ], and an annotation of search terms tested but not used [ 4 ] were identified as unique items in four documents.

The Cochrane Handbook was the only guidance document to note that the full search strategies for each database should be included in the Additional file 1 of the review [ 9 ].

All guidance documents should ultimately deliver completed systematic reviews that fulfil the requirements of the PRISMA reporting guidelines [ 108 ]. The guidance broadly requires the reporting of data that corresponds with the requirements of the PRISMA statement although documents typically ask for diverse and additional items [ 108 ]. In 2008, Sampson et al. observed a lack of consensus on reporting search methods in systematic reviews [ 109 ] and this remains the case as of 2017, as evidenced in the guidance documents, and in spite of the publication of the PRISMA guidelines in 2009 [ 110 ]. It is unclear why the collective guidance does not more explicitly endorse adherence to the PRISMA guidance.

Reporting of literature searching is a key area in systematic reviews since it sets out clearly what was done and how the conclusions of the review can be believed [ 52 , 109 ]. Despite strong endorsement in the guidance documents, specifically supported in PRISMA guidance, and other related reporting standards too (such as ENTREQ for qualitative evidence synthesis, STROBE for reviews of observational studies), authors still highlight the prevalence of poor standards of literature search reporting [ 31 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 ]. To explore issues experienced by authors in reporting literature searches, and look at uptake of PRISMA, Radar et al. [ 120 ] surveyed over 260 review authors to determine common problems and their work summaries the practical aspects of reporting literature searching [ 120 ]. Atkinson et al. [ 121 ] have also analysed reporting standards for literature searching, summarising recommendations and gaps for reporting search strategies [ 121 ].

One area that is less well covered by the guidance, but nevertheless appears in this literature, is the quality appraisal or peer review of literature search strategies. The PRESS checklist is the most prominent and it aims to develop evidence-based guidelines to peer review of electronic search strategies [ 5 , 122 , 123 ]. A corresponding guideline for documentation of supplementary search methods does not yet exist although this idea is currently being explored.

How the reporting of the literature searching process corresponds to critical appraisal tools is an area for further research. In the survey undertaken by Radar et al. (2014), 86% of survey respondents (153/178) identified a need for further guidance on what aspects of the literature search process to report [ 120 ]. The PRISMA statement offers a brief summary of what to report but little practical guidance on how to report it [ 108 ]. Critical appraisal tools for systematic reviews, such as AMSTAR 2 (Shea et al. [ 124 ]) and ROBIS (Whiting et al. [ 125 ]), can usefully be read alongside PRISMA guidance, since they offer greater detail on how the reporting of the literature search will be appraised and, therefore, they offer a proxy on what to report [ 124 , 125 ]. Further research in the form of a study which undertakes a comparison between PRISMA and quality appraisal checklists for systematic reviews would seem to begin addressing the call, identified by Radar et al., for further guidance on what to report [ 120 ].

Limitations

Other handbooks exist.

A potential limitation of this literature review is the focus on guidance produced in Europe (the UK specifically) and Australia. We justify the decision for our selection of the nine guidance documents reviewed in this literature review in section “ Identifying guidance ”. In brief, these nine guidance documents were selected as the most relevant health care guidance that inform UK systematic reviewing practice, given that the UK occupies a prominent position in the science of health information retrieval. We acknowledge the existence of other guidance documents, such as those from North America (e.g. the Agency for Healthcare Research and Quality (AHRQ) [ 126 ], The Institute of Medicine [ 127 ] and the guidance and resources produced by the Canadian Agency for Drugs and Technologies in Health (CADTH) [ 128 ]). We comment further on this directly below.

The handbooks are potentially linked to one another

What is not clear is the extent to which the guidance documents inter-relate or provide guidance uniquely. The Cochrane Handbook, first published in 1994, is notably a key source of reference in guidance and systematic reviews beyond Cochrane reviews. It is not clear to what extent broadening the sample of guidance handbooks to include North American handbooks, and guidance handbooks from other relevant countries too, would alter the findings of this literature review or develop further support for the process model. Since we cannot be clear, we raise this as a potential limitation of this literature review. On our initial review of a sample of North American, and other, guidance documents (before selecting the guidance documents considered in this review), however, we do not consider that the inclusion of these further handbooks would alter significantly the findings of this literature review.

This is a literature review

A further limitation of this review was that the review of published studies is not a systematic review of the evidence for each key stage. It is possible that other relevant studies could help contribute to the exploration and development of the key stages identified in this review.

This literature review would appear to demonstrate the existence of a shared model of the literature searching process in systematic reviews. We call this model ‘the conventional approach’, since it appears to be common convention in nine different guidance documents.

The findings reported above reveal eight key stages in the process of literature searching for systematic reviews. These key stages are consistently reported in the nine guidance documents which suggests consensus on the key stages of literature searching, and therefore the process of literature searching as a whole, in systematic reviews.

In Table 2 , we demonstrate consensus regarding the application of literature search methods. All guidance documents distinguish between primary and supplementary search methods. Bibliographic database searching is consistently the first method of literature searching referenced in each guidance document. Whilst the guidance uniformly supports the use of supplementary search methods, there is little evidence for a consistent process with diverse guidance across documents. This may reflect differences in the core focus across each document, linked to differences in identifying effectiveness studies or qualitative studies, for instance.

Eight of the nine guidance documents reported on the aims of literature searching. The shared understanding was that literature searching should be thorough and comprehensive in its aim and that this process should be reported transparently so that that it could be reproduced. Whilst only three documents explicitly link this understanding to minimising bias, it is clear that comprehensive literature searching is implicitly linked to ‘not missing relevant studies’ which is approximately the same point.

Defining the key stages in this review helps categorise the scholarship available, and it prioritises areas for development or further study. The supporting studies on preparing for literature searching (key stage three, ‘preparation’) were, for example, comparatively few, and yet this key stage represents a decisive moment in literature searching for systematic reviews. It is where search strategy structure is determined, search terms are chosen or discarded, and the resources to be searched are selected. Information specialists, librarians and researchers, are well placed to develop these and other areas within the key stages we identify.

This review calls for further research to determine the suitability of using the conventional approach. The publication dates of the guidance documents which underpin the conventional approach may raise questions as to whether the process which they each report remains valid for current systematic literature searching. In addition, it may be useful to test whether it is desirable to use the same process model of literature searching for qualitative evidence synthesis as that for reviews of intervention effectiveness, which this literature review demonstrates is presently recommended best practice.

Abbreviations

Behaviour of interest; Health context; Exclusions; Models or Theories

Cochrane Database of Systematic Reviews

The Cochrane Central Register of Controlled Trials

Database of Abstracts of Reviews of Effects

Enhancing transparency in reporting the synthesis of qualitative research

Institute for Quality and Efficiency in Healthcare

National Institute for Clinical Excellence

Population, Intervention, Comparator, Outcome

Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Setting, Perspective, Intervention, Comparison, Evaluation

Sample, Phenomenon of Interest, Design, Evaluation, Research type

STrengthening the Reporting of OBservational studies in Epidemiology

Trial Search Co-ordinators

Booth A. Unpacking your literature search toolbox: on search styles and tactics. Health Information & Libraries Journal. 2008;25(4):313–7.

Article   Google Scholar  

Petticrew M, Roberts H. Systematic reviews in the social sciences: a practical guide. Oxford: Blackwell Publishing Ltd; 2006.

Book   Google Scholar  

Institute for Quality and Efficiency in Health Care (IQWiG). IQWiG Methods Resources. 7 Information retrieval 2014 [Available from: https://www.ncbi.nlm.nih.gov/books/NBK385787/ .

NICE: National Institute for Health and Care Excellence. Developing NICE guidelines: the manual 2014. Available from: https://www.nice.org.uk/media/default/about/what-we-do/our-programmes/developing-nice-guidelines-the-manual.pdf .

Sampson M. MJ, Lefebvre C, Moher D, Grimshaw J. Peer Review of Electronic Search Strategies: PRESS; 2008.

Google Scholar  

Centre for Reviews & Dissemination. Systematic reviews – CRD’s guidance for undertaking reviews in healthcare. York: Centre for Reviews and Dissemination, University of York; 2009.

eunetha: European Network for Health Technology Assesment Process of information retrieval for systematic reviews and health technology assessments on clinical effectiveness 2016. Available from: http://www.eunethta.eu/sites/default/files/Guideline_Information_Retrieval_V1-1.pdf .

Kugley SWA, Thomas J, Mahood Q, Jørgensen AMK, Hammerstrøm K, Sathe N. Searching for studies: a guide to information retrieval for Campbell systematic reviews. Oslo: Campbell Collaboration. 2017; Available from: https://www.campbellcollaboration.org/library/searching-for-studies-information-retrieval-guide-campbell-reviews.html

Lefebvre C, Manheimer E, Glanville J. Chapter 6: searching for studies. In: JPT H, Green S, editors. Cochrane Handbook for Systematic Reviews of Interventions; 2011.

Collaboration for Environmental Evidence. Guidelines for Systematic Review and Evidence Synthesis in Environmental Management.: Environmental Evidence:; 2013. Available from: http://www.environmentalevidence.org/wp-content/uploads/2017/01/Review-guidelines-version-4.2-final-update.pdf .

The Joanna Briggs Institute. Joanna Briggs institute reviewers’ manual. 2014th ed: the Joanna Briggs institute; 2014. Available from: https://joannabriggs.org/assets/docs/sumari/ReviewersManual-2014.pdf

Beverley CA, Booth A, Bath PA. The role of the information specialist in the systematic review process: a health information case study. Health Inf Libr J. 2003;20(2):65–74.

Article   CAS   Google Scholar  

Harris MR. The librarian's roles in the systematic review process: a case study. Journal of the Medical Library Association. 2005;93(1):81–7.

PubMed   PubMed Central   Google Scholar  

Egger JB. Use of recommended search strategies in systematic reviews and the impact of librarian involvement: a cross-sectional survey of recent authors. PLoS One. 2015;10(5):e0125931.

Li L, Tian J, Tian H, Moher D, Liang F, Jiang T, et al. Network meta-analyses could be improved by searching more sources and by involving a librarian. J Clin Epidemiol. 2014;67(9):1001–7.

Article   PubMed   Google Scholar  

McGowan J, Sampson M. Systematic reviews need systematic searchers. J Med Libr Assoc. 2005;93(1):74–80.

Rethlefsen ML, Farrell AM, Osterhaus Trzasko LC, Brigham TJ. Librarian co-authors correlated with higher quality reported search strategies in general internal medicine systematic reviews. J Clin Epidemiol. 2015;68(6):617–26.

Weller AC. Mounting evidence that librarians are essential for comprehensive literature searches for meta-analyses and Cochrane reports. J Med Libr Assoc. 2004;92(2):163–4.

Swinkels A, Briddon J, Hall J. Two physiotherapists, one librarian and a systematic literature review: collaboration in action. Health Info Libr J. 2006;23(4):248–56.

Foster M. An overview of the role of librarians in systematic reviews: from expert search to project manager. EAHIL. 2015;11(3):3–7.

Lawson L. OPERATING OUTSIDE LIBRARY WALLS 2004.

Vassar M, Yerokhin V, Sinnett PM, Weiher M, Muckelrath H, Carr B, et al. Database selection in systematic reviews: an insight through clinical neurology. Health Inf Libr J. 2017;34(2):156–64.

Townsend WA, Anderson PF, Ginier EC, MacEachern MP, Saylor KM, Shipman BL, et al. A competency framework for librarians involved in systematic reviews. Journal of the Medical Library Association : JMLA. 2017;105(3):268–75.

Cooper ID, Crum JA. New activities and changing roles of health sciences librarians: a systematic review, 1990-2012. Journal of the Medical Library Association : JMLA. 2013;101(4):268–77.

Crum JA, Cooper ID. Emerging roles for biomedical librarians: a survey of current practice, challenges, and changes. Journal of the Medical Library Association : JMLA. 2013;101(4):278–86.

Dudden RF, Protzko SL. The systematic review team: contributions of the health sciences librarian. Med Ref Serv Q. 2011;30(3):301–15.

Golder S, Loke Y, McIntosh HM. Poor reporting and inadequate searches were apparent in systematic reviews of adverse effects. J Clin Epidemiol. 2008;61(5):440–8.

Maggio LA, Tannery NH, Kanter SL. Reproducibility of literature search reporting in medical education reviews. Academic medicine : journal of the Association of American Medical Colleges. 2011;86(8):1049–54.

Meert D, Torabi N, Costella J. Impact of librarians on reporting of the literature searching component of pediatric systematic reviews. Journal of the Medical Library Association : JMLA. 2016;104(4):267–77.

Morris M, Boruff JT, Gore GC. Scoping reviews: establishing the role of the librarian. Journal of the Medical Library Association : JMLA. 2016;104(4):346–54.

Koffel JB, Rethlefsen ML. Reproducibility of search strategies is poor in systematic reviews published in high-impact pediatrics, cardiology and surgery journals: a cross-sectional study. PLoS One. 2016;11(9):e0163309.

Article   PubMed   PubMed Central   CAS   Google Scholar  

Fehrmann P, Thomas J. Comprehensive computer searches and reporting in systematic reviews. Research Synthesis Methods. 2011;2(1):15–32.

Booth A. Searching for qualitative research for inclusion in systematic reviews: a structured methodological review. Systematic Reviews. 2016;5(1):74.

Article   PubMed   PubMed Central   Google Scholar  

Egger M, Juni P, Bartlett C, Holenstein F, Sterne J. How important are comprehensive literature searches and the assessment of trial quality in systematic reviews? Empirical study. Health technology assessment (Winchester, England). 2003;7(1):1–76.

Tricco AC, Tetzlaff J, Sampson M, Fergusson D, Cogo E, Horsley T, et al. Few systematic reviews exist documenting the extent of bias: a systematic review. J Clin Epidemiol. 2008;61(5):422–34.

Booth A. How much searching is enough? Comprehensive versus optimal retrieval for technology assessments. Int J Technol Assess Health Care. 2010;26(4):431–5.

Papaioannou D, Sutton A, Carroll C, Booth A, Wong R. Literature searching for social science systematic reviews: consideration of a range of search techniques. Health Inf Libr J. 2010;27(2):114–22.

Petticrew M. Time to rethink the systematic review catechism? Moving from ‘what works’ to ‘what happens’. Systematic Reviews. 2015;4(1):36.

Betrán AP, Say L, Gülmezoglu AM, Allen T, Hampson L. Effectiveness of different databases in identifying studies for systematic reviews: experience from the WHO systematic review of maternal morbidity and mortality. BMC Med Res Methodol. 2005;5

Felson DT. Bias in meta-analytic research. J Clin Epidemiol. 1992;45(8):885–92.

Article   PubMed   CAS   Google Scholar  

Franco A, Malhotra N, Simonovits G. Publication bias in the social sciences: unlocking the file drawer. Science. 2014;345(6203):1502–5.

Hartling L, Featherstone R, Nuspl M, Shave K, Dryden DM, Vandermeer B. Grey literature in systematic reviews: a cross-sectional study of the contribution of non-English reports, unpublished studies and dissertations to the results of meta-analyses in child-relevant reviews. BMC Med Res Methodol. 2017;17(1):64.

Schmucker CM, Blümle A, Schell LK, Schwarzer G, Oeller P, Cabrera L, et al. Systematic review finds that study data not published in full text articles have unclear impact on meta-analyses results in medical research. PLoS One. 2017;12(4):e0176210.

Egger M, Zellweger-Zahner T, Schneider M, Junker C, Lengeler C, Antes G. Language bias in randomised controlled trials published in English and German. Lancet (London, England). 1997;350(9074):326–9.

Moher D, Pham B, Lawson ML, Klassen TP. The inclusion of reports of randomised trials published in languages other than English in systematic reviews. Health technology assessment (Winchester, England). 2003;7(41):1–90.

Pham B, Klassen TP, Lawson ML, Moher D. Language of publication restrictions in systematic reviews gave different results depending on whether the intervention was conventional or complementary. J Clin Epidemiol. 2005;58(8):769–76.

Mills EJ, Kanters S, Thorlund K, Chaimani A, Veroniki A-A, Ioannidis JPA. The effects of excluding treatments from network meta-analyses: survey. BMJ : British Medical Journal. 2013;347

Hartling L, Featherstone R, Nuspl M, Shave K, Dryden DM, Vandermeer B. The contribution of databases to the results of systematic reviews: a cross-sectional study. BMC Med Res Methodol. 2016;16(1):127.

van Driel ML, De Sutter A, De Maeseneer J, Christiaens T. Searching for unpublished trials in Cochrane reviews may not be worth the effort. J Clin Epidemiol. 2009;62(8):838–44.e3.

Buchberger B, Krabbe L, Lux B, Mattivi JT. Evidence mapping for decision making: feasibility versus accuracy - when to abandon high sensitivity in electronic searches. German medical science : GMS e-journal. 2016;14:Doc09.

Lorenc T, Pearson M, Jamal F, Cooper C, Garside R. The role of systematic reviews of qualitative evidence in evaluating interventions: a case study. Research Synthesis Methods. 2012;3(1):1–10.

Gough D. Weight of evidence: a framework for the appraisal of the quality and relevance of evidence. Res Pap Educ. 2007;22(2):213–28.

Barroso J, Gollop CJ, Sandelowski M, Meynell J, Pearce PF, Collins LJ. The challenges of searching for and retrieving qualitative studies. West J Nurs Res. 2003;25(2):153–78.

Britten N, Garside R, Pope C, Frost J, Cooper C. Asking more of qualitative synthesis: a response to Sally Thorne. Qual Health Res. 2017;27(9):1370–6.

Booth A, Carroll C. Systematic searching for theory to inform systematic reviews: is it feasible? Is it desirable? Health Info Libr J. 2015;32(3):220–35.

Kwon Y, Powelson SE, Wong H, Ghali WA, Conly JM. An assessment of the efficacy of searching in biomedical databases beyond MEDLINE in identifying studies for a systematic review on ward closures as an infection control intervention to control outbreaks. Syst Rev. 2014;3:135.

Nussbaumer-Streit B, Klerings I, Wagner G, Titscher V, Gartlehner G. Assessing the validity of abbreviated literature searches for rapid reviews: protocol of a non-inferiority and meta-epidemiologic study. Systematic Reviews. 2016;5:197.

Wagner G, Nussbaumer-Streit B, Greimel J, Ciapponi A, Gartlehner G. Trading certainty for speed - how much uncertainty are decisionmakers and guideline developers willing to accept when using rapid reviews: an international survey. BMC Med Res Methodol. 2017;17(1):121.

Ogilvie D, Hamilton V, Egan M, Petticrew M. Systematic reviews of health effects of social interventions: 1. Finding the evidence: how far should you go? J Epidemiol Community Health. 2005;59(9):804–8.

Royle P, Milne R. Literature searching for randomized controlled trials used in Cochrane reviews: rapid versus exhaustive searches. Int J Technol Assess Health Care. 2003;19(4):591–603.

Pearson M, Moxham T, Ashton K. Effectiveness of search strategies for qualitative research about barriers and facilitators of program delivery. Eval Health Prof. 2011;34(3):297–308.

Levay P, Raynor M, Tuvey D. The Contributions of MEDLINE, Other Bibliographic Databases and Various Search Techniques to NICE Public Health Guidance. 2015. 2015;10(1):19.

Nussbaumer-Streit B, Klerings I, Wagner G, Heise TL, Dobrescu AI, Armijo-Olivo S, et al. Abbreviated literature searches were viable alternatives to comprehensive searches: a meta-epidemiological study. J Clin Epidemiol. 2018;102:1–11.

Briscoe S, Cooper C, Glanville J, Lefebvre C. The loss of the NHS EED and DARE databases and the effect on evidence synthesis and evaluation. Res Synth Methods. 2017;8(3):256–7.

Stansfield C, O'Mara-Eves A, Thomas J. Text mining for search term development in systematic reviewing: A discussion of some methods and challenges. Research Synthesis Methods.n/a-n/a.

Petrova M, Sutcliffe P, Fulford KW, Dale J. Search terms and a validated brief search filter to retrieve publications on health-related values in Medline: a word frequency analysis study. Journal of the American Medical Informatics Association : JAMIA. 2012;19(3):479–88.

Stansfield C, Thomas J, Kavanagh J. 'Clustering' documents automatically to support scoping reviews of research: a case study. Res Synth Methods. 2013;4(3):230–41.

PubMed   Google Scholar  

Methley AM, Campbell S, Chew-Graham C, McNally R, Cheraghi-Sohi S. PICO, PICOS and SPIDER: a comparison study of specificity and sensitivity in three search tools for qualitative systematic reviews. BMC Health Serv Res. 2014;14:579.

Andrew B. Clear and present questions: formulating questions for evidence based practice. Library Hi Tech. 2006;24(3):355–68.

Cooke A, Smith D, Booth A. Beyond PICO: the SPIDER tool for qualitative evidence synthesis. Qual Health Res. 2012;22(10):1435–43.

Whiting P, Westwood M, Bojke L, Palmer S, Richardson G, Cooper J, et al. Clinical effectiveness and cost-effectiveness of tests for the diagnosis and investigation of urinary tract infection in children: a systematic review and economic model. Health technology assessment (Winchester, England). 2006;10(36):iii-iv, xi-xiii, 1–154.

Cooper C, Levay P, Lorenc T, Craig GM. A population search filter for hard-to-reach populations increased search efficiency for a systematic review. J Clin Epidemiol. 2014;67(5):554–9.

Hausner E, Waffenschmidt S, Kaiser T, Simon M. Routine development of objectively derived search strategies. Systematic Reviews. 2012;1(1):19.

Hausner E, Guddat C, Hermanns T, Lampert U, Waffenschmidt S. Prospective comparison of search strategies for systematic reviews: an objective approach yielded higher sensitivity than a conceptual one. J Clin Epidemiol. 2016;77:118–24.

Craven J, Levay P. Recording database searches for systematic reviews - what is the value of adding a narrative to peer-review checklists? A case study of nice interventional procedures guidance. Evid Based Libr Inf Pract. 2011;6(4):72–87.

Wright K, Golder S, Lewis-Light K. What value is the CINAHL database when searching for systematic reviews of qualitative studies? Syst Rev. 2015;4:104.

Beckles Z, Glover S, Ashe J, Stockton S, Boynton J, Lai R, et al. Searching CINAHL did not add value to clinical questions posed in NICE guidelines. J Clin Epidemiol. 2013;66(9):1051–7.

Cooper C, Rogers M, Bethel A, Briscoe S, Lowe J. A mapping review of the literature on UK-focused health and social care databases. Health Inf Libr J. 2015;32(1):5–22.

Younger P, Boddy K. When is a search not a search? A comparison of searching the AMED complementary health database via EBSCOhost, OVID and DIALOG. Health Inf Libr J. 2009;26(2):126–35.

Lam MT, McDiarmid M. Increasing number of databases searched in systematic reviews and meta-analyses between 1994 and 2014. Journal of the Medical Library Association : JMLA. 2016;104(4):284–9.

Bethel A, editor Search summary tables for systematic reviews: results and findings. HLC Conference 2017a.

Aagaard T, Lund H, Juhl C. Optimizing literature search in systematic reviews - are MEDLINE, EMBASE and CENTRAL enough for identifying effect studies within the area of musculoskeletal disorders? BMC Med Res Methodol. 2016;16(1):161.

Adams CE, Frederick K. An investigation of the adequacy of MEDLINE searches for randomized controlled trials (RCTs) of the effects of mental health care. Psychol Med. 1994;24(3):741–8.

Kelly L, St Pierre-Hansen N. So many databases, such little clarity: searching the literature for the topic aboriginal. Canadian family physician Medecin de famille canadien. 2008;54(11):1572–3.

Lawrence DW. What is lost when searching only one literature database for articles relevant to injury prevention and safety promotion? Injury Prevention. 2008;14(6):401–4.

Lemeshow AR, Blum RE, Berlin JA, Stoto MA, Colditz GA. Searching one or two databases was insufficient for meta-analysis of observational studies. J Clin Epidemiol. 2005;58(9):867–73.

Sampson M, Barrowman NJ, Moher D, Klassen TP, Pham B, Platt R, et al. Should meta-analysts search Embase in addition to Medline? J Clin Epidemiol. 2003;56(10):943–55.

Stevinson C, Lawlor DA. Searching multiple databases for systematic reviews: added value or diminishing returns? Complementary Therapies in Medicine. 2004;12(4):228–32.

Suarez-Almazor ME, Belseck E, Homik J, Dorgan M, Ramos-Remus C. Identifying clinical trials in the medical literature with electronic databases: MEDLINE alone is not enough. Control Clin Trials. 2000;21(5):476–87.

Taylor B, Wylie E, Dempster M, Donnelly M. Systematically retrieving research: a case study evaluating seven databases. Res Soc Work Pract. 2007;17(6):697–706.

Beyer FR, Wright K. Can we prioritise which databases to search? A case study using a systematic review of frozen shoulder management. Health Info Libr J. 2013;30(1):49–58.

Duffy S, de Kock S, Misso K, Noake C, Ross J, Stirk L. Supplementary searches of PubMed to improve currency of MEDLINE and MEDLINE in-process searches via Ovid. Journal of the Medical Library Association : JMLA. 2016;104(4):309–12.

Katchamart W, Faulkner A, Feldman B, Tomlinson G, Bombardier C. PubMed had a higher sensitivity than Ovid-MEDLINE in the search for systematic reviews. J Clin Epidemiol. 2011;64(7):805–7.

Cooper C, Lovell R, Husk K, Booth A, Garside R. Supplementary search methods were more effective and offered better value than bibliographic database searching: a case study from public health and environmental enhancement (in Press). Research Synthesis Methods. 2017;

Cooper C, Booth, A., Britten, N., Garside, R. A comparison of results of empirical studies of supplementary search techniques and recommendations in review methodology handbooks: A methodological review. (In Press). BMC Systematic Reviews. 2017.

Greenhalgh T, Peacock R. Effectiveness and efficiency of search methods in systematic reviews of complex evidence: audit of primary sources. BMJ (Clinical research ed). 2005;331(7524):1064–5.

Article   PubMed Central   Google Scholar  

Hinde S, Spackman E. Bidirectional citation searching to completion: an exploration of literature searching methods. PharmacoEconomics. 2015;33(1):5–11.

Levay P, Ainsworth N, Kettle R, Morgan A. Identifying evidence for public health guidance: a comparison of citation searching with web of science and Google scholar. Res Synth Methods. 2016;7(1):34–45.

McManus RJ, Wilson S, Delaney BC, Fitzmaurice DA, Hyde CJ, Tobias RS, et al. Review of the usefulness of contacting other experts when conducting a literature search for systematic reviews. BMJ (Clinical research ed). 1998;317(7172):1562–3.

Westphal A, Kriston L, Holzel LP, Harter M, von Wolff A. Efficiency and contribution of strategies for finding randomized controlled trials: a case study from a systematic review on therapeutic interventions of chronic depression. Journal of public health research. 2014;3(2):177.

Matthews EJ, Edwards AG, Barker J, Bloor M, Covey J, Hood K, et al. Efficient literature searching in diffuse topics: lessons from a systematic review of research on communicating risk to patients in primary care. Health Libr Rev. 1999;16(2):112–20.

Bethel A. Endnote Training (YouTube Videos) 2017b [Available from: http://medicine.exeter.ac.uk/esmi/workstreams/informationscience/is_resources,_guidance_&_advice/ .

Bramer WM, Giustini D, de Jonge GB, Holland L, Bekhuis T. De-duplication of database search results for systematic reviews in EndNote. Journal of the Medical Library Association : JMLA. 2016;104(3):240–3.

Bramer WM, Milic J, Mast F. Reviewing retrieved references for inclusion in systematic reviews using EndNote. Journal of the Medical Library Association : JMLA. 2017;105(1):84–7.

Gall C, Brahmi FA. Retrieval comparison of EndNote to search MEDLINE (Ovid and PubMed) versus searching them directly. Medical reference services quarterly. 2004;23(3):25–32.

Ahmed KK, Al Dhubaib BE. Zotero: a bibliographic assistant to researcher. J Pharmacol Pharmacother. 2011;2(4):303–5.

Coar JT, Sewell JP. Zotero: harnessing the power of a personal bibliographic manager. Nurse Educ. 2010;35(5):205–7.

Moher D, Liberati A, Tetzlaff J, Altman DG, The PG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009;6(7):e1000097.

Sampson M, McGowan J, Tetzlaff J, Cogo E, Moher D. No consensus exists on search reporting methods for systematic reviews. J Clin Epidemiol. 2008;61(8):748–54.

Toews LC. Compliance of systematic reviews in veterinary journals with preferred reporting items for systematic reviews and meta-analysis (PRISMA) literature search reporting guidelines. Journal of the Medical Library Association : JMLA. 2017;105(3):233–9.

Booth A. "brimful of STARLITE": toward standards for reporting literature searches. Journal of the Medical Library Association : JMLA. 2006;94(4):421–9. e205

Faggion CM Jr, Wu YC, Tu YK, Wasiak J. Quality of search strategies reported in systematic reviews published in stereotactic radiosurgery. Br J Radiol. 2016;89(1062):20150878.

Mullins MM, DeLuca JB, Crepaz N, Lyles CM. Reporting quality of search methods in systematic reviews of HIV behavioral interventions (2000–2010): are the searches clearly explained, systematic and reproducible? Research Synthesis Methods. 2014;5(2):116–30.

Yoshii A, Plaut DA, McGraw KA, Anderson MJ, Wellik KE. Analysis of the reporting of search strategies in Cochrane systematic reviews. Journal of the Medical Library Association : JMLA. 2009;97(1):21–9.

Bigna JJ, Um LN, Nansseu JR. A comparison of quality of abstracts of systematic reviews including meta-analysis of randomized controlled trials in high-impact general medicine journals before and after the publication of PRISMA extension for abstracts: a systematic review and meta-analysis. Syst Rev. 2016;5(1):174.

Akhigbe T, Zolnourian A, Bulters D. Compliance of systematic reviews articles in brain arteriovenous malformation with PRISMA statement guidelines: review of literature. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2017;39:45–8.

Tao KM, Li XQ, Zhou QH, Moher D, Ling CQ, Yu WF. From QUOROM to PRISMA: a survey of high-impact medical journals' instructions to authors and a review of systematic reviews in anesthesia literature. PLoS One. 2011;6(11):e27611.

Wasiak J, Tyack Z, Ware R. Goodwin N. Jr. Poor methodological quality and reporting standards of systematic reviews in burn care management. International wound journal: Faggion CM; 2016.

Tam WW, Lo KK, Khalechelvam P. Endorsement of PRISMA statement and quality of systematic reviews and meta-analyses published in nursing journals: a cross-sectional study. BMJ Open. 2017;7(2):e013905.

Rader T, Mann M, Stansfield C, Cooper C, Sampson M. Methods for documenting systematic review searches: a discussion of common issues. Res Synth Methods. 2014;5(2):98–115.

Atkinson KM, Koenka AC, Sanchez CE, Moshontz H, Cooper H. Reporting standards for literature searches and report inclusion criteria: making research syntheses more transparent and easy to replicate. Res Synth Methods. 2015;6(1):87–95.

McGowan J, Sampson M, Salzwedel DM, Cogo E, Foerster V, Lefebvre C. PRESS peer review of electronic search strategies: 2015 guideline statement. J Clin Epidemiol. 2016;75:40–6.

Sampson M, McGowan J, Cogo E, Grimshaw J, Moher D, Lefebvre C. An evidence-based practice guideline for the peer review of electronic search strategies. J Clin Epidemiol. 2009;62(9):944–52.

Shea BJ, Reeves BC, Wells G, Thuku M, Hamel C, Moran J, et al. AMSTAR 2: a critical appraisal tool for systematic reviews that include randomised or non-randomised studies of healthcare interventions, or both. BMJ (Clinical research ed). 2017;358.

Whiting P, Savović J, Higgins JPT, Caldwell DM, Reeves BC, Shea B, et al. ROBIS: a new tool to assess risk of bias in systematic reviews was developed. J Clin Epidemiol. 2016;69:225–34.

Relevo R, Balshem H. Finding evidence for comparing medical interventions: AHRQ and the effective health care program. J Clin Epidemiol. 2011;64(11):1168–77.

Medicine Io. Standards for Systematic Reviews 2011 [Available from: http://www.nationalacademies.org/hmd/Reports/2011/Finding-What-Works-in-Health-Care-Standards-for-Systematic-Reviews/Standards.aspx .

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Acknowledgements

CC acknowledges the supervision offered by Professor Chris Hyde.

This publication forms a part of CC’s PhD. CC’s PhD was funded through the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme (Project Number 16/54/11). The open access fee for this publication was paid for by Exeter Medical School.

RG and NB were partially supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula.

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CC conceived the idea for this study and wrote the first draft of the manuscript. CC discussed this publication in PhD supervision with AB and separately with JVC. CC revised the publication with input and comments from AB, JVC, RG and NB. All authors revised the manuscript prior to submission. All authors read and approved the final manuscript.

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Appendix tables and PubMed search strategy. Key studies used for pearl growing per key stage, working data extraction tables and the PubMed search strategy. (DOCX 30 kb)

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Cooper, C., Booth, A., Varley-Campbell, J. et al. Defining the process to literature searching in systematic reviews: a literature review of guidance and supporting studies. BMC Med Res Methodol 18 , 85 (2018). https://doi.org/10.1186/s12874-018-0545-3

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Research Methods

• Getting Started
• Literature Review Research
• Research Design
• Research Design By Discipline
• SAGE Research Methods
• Teaching with SAGE Research Methods

Literature Review

• What is a Literature Review?
• What is NOT a Literature Review?
• Purposes of a Literature Review
• Types of Literature Reviews
• Literature Reviews vs. Systematic Reviews
• Systematic vs. Meta-Analysis

Literature Review  is a comprehensive survey of the works published in a particular field of study or line of research, usually over a specific period of time, in the form of an in-depth, critical bibliographic essay or annotated list in which attention is drawn to the most significant works.

Also, we can define a literature review as the collected body of scholarly works related to a topic:

• Summarizes and analyzes previous research relevant to a topic
• Includes scholarly books and articles published in academic journals
• Can be an specific scholarly paper or a section in a research paper

The objective of a Literature Review is to find previous published scholarly works relevant to an specific topic

• Help gather ideas or information
• Keep up to date in current trends and findings
• Help develop new questions

A literature review is important because it:

• Explains the background of research on a topic.
• Demonstrates why a topic is significant to a subject area.
• Helps focus your own research questions or problems
• Discovers relationships between research studies/ideas.
• Suggests unexplored ideas or populations
• Identifies major themes, concepts, and researchers on a topic.
• Tests assumptions; may help counter preconceived ideas and remove unconscious bias.
• Identifies critical gaps, points of disagreement, or potentially flawed methodology or theoretical approaches.
• Indicates potential directions for future research.

All content in this section is from Literature Review Research from Old Dominion University 

Keep in mind the following, a literature review is NOT:

Not an essay 

Not an annotated bibliography  in which you summarize each article that you have reviewed.  A literature review goes beyond basic summarizing to focus on the critical analysis of the reviewed works and their relationship to your research question.

Not a research paper   where you select resources to support one side of an issue versus another.  A lit review should explain and consider all sides of an argument in order to avoid bias, and areas of agreement and disagreement should be highlighted.

A literature review serves several purposes. For example, it

• provides thorough knowledge of previous studies; introduces seminal works.
• helps focus one’s own research topic.
• identifies a conceptual framework for one’s own research questions or problems; indicates potential directions for future research.
• suggests previously unused or underused methodologies, designs, quantitative and qualitative strategies.
• identifies gaps in previous studies; identifies flawed methodologies and/or theoretical approaches; avoids replication of mistakes.
• helps the researcher avoid repetition of earlier research.
• suggests unexplored populations.
• determines whether past studies agree or disagree; identifies controversy in the literature.
• tests assumptions; may help counter preconceived ideas and remove unconscious bias.

As Kennedy (2007) notes*, it is important to think of knowledge in a given field as consisting of three layers. First, there are the primary studies that researchers conduct and publish. Second are the reviews of those studies that summarize and offer new interpretations built from and often extending beyond the original studies. Third, there are the perceptions, conclusions, opinion, and interpretations that are shared informally that become part of the lore of field. In composing a literature review, it is important to note that it is often this third layer of knowledge that is cited as "true" even though it often has only a loose relationship to the primary studies and secondary literature reviews.

Given this, while literature reviews are designed to provide an overview and synthesis of pertinent sources you have explored, there are several approaches to how they can be done, depending upon the type of analysis underpinning your study. Listed below are definitions of types of literature reviews:

Argumentative Review      This form examines literature selectively in order to support or refute an argument, deeply imbedded assumption, or philosophical problem already established in the literature. The purpose is to develop a body of literature that establishes a contrarian viewpoint. Given the value-laden nature of some social science research [e.g., educational reform; immigration control], argumentative approaches to analyzing the literature can be a legitimate and important form of discourse. However, note that they can also introduce problems of bias when they are used to to make summary claims of the sort found in systematic reviews.

Integrative Review      Considered a form of research that reviews, critiques, and synthesizes representative literature on a topic in an integrated way such that new frameworks and perspectives on the topic are generated. The body of literature includes all studies that address related or identical hypotheses. A well-done integrative review meets the same standards as primary research in regard to clarity, rigor, and replication.

Historical Review      Few things rest in isolation from historical precedent. Historical reviews are focused on examining research throughout a period of time, often starting with the first time an issue, concept, theory, phenomena emerged in the literature, then tracing its evolution within the scholarship of a discipline. The purpose is to place research in a historical context to show familiarity with state-of-the-art developments and to identify the likely directions for future research.

Methodological Review      A review does not always focus on what someone said [content], but how they said it [method of analysis]. This approach provides a framework of understanding at different levels (i.e. those of theory, substantive fields, research approaches and data collection and analysis techniques), enables researchers to draw on a wide variety of knowledge ranging from the conceptual level to practical documents for use in fieldwork in the areas of ontological and epistemological consideration, quantitative and qualitative integration, sampling, interviewing, data collection and data analysis, and helps highlight many ethical issues which we should be aware of and consider as we go through our study.

Systematic Review      This form consists of an overview of existing evidence pertinent to a clearly formulated research question, which uses pre-specified and standardized methods to identify and critically appraise relevant research, and to collect, report, and analyse data from the studies that are included in the review. Typically it focuses on a very specific empirical question, often posed in a cause-and-effect form, such as "To what extent does A contribute to B?"

Theoretical Review      The purpose of this form is to concretely examine the corpus of theory that has accumulated in regard to an issue, concept, theory, phenomena. The theoretical literature review help establish what theories already exist, the relationships between them, to what degree the existing theories have been investigated, and to develop new hypotheses to be tested. Often this form is used to help establish a lack of appropriate theories or reveal that current theories are inadequate for explaining new or emerging research problems. The unit of analysis can focus on a theoretical concept or a whole theory or framework.

* Kennedy, Mary M. "Defining a Literature."  Educational Researcher  36 (April 2007): 139-147.

All content in this section is from The Literature Review created by Dr. Robert Larabee USC

Robinson, P. and Lowe, J. (2015),  Literature reviews vs systematic reviews.  Australian and New Zealand Journal of Public Health, 39: 103-103. doi: 10.1111/1753-6405.12393

What's in the name? The difference between a Systematic Review and a Literature Review, and why it matters . By Lynn Kysh from University of Southern California

Systematic review or meta-analysis?

A  systematic review  answers a defined research question by collecting and summarizing all empirical evidence that fits pre-specified eligibility criteria.

A  meta-analysis  is the use of statistical methods to summarize the results of these studies.

Systematic reviews, just like other research articles, can be of varying quality. They are a significant piece of work (the Centre for Reviews and Dissemination at York estimates that a team will take 9-24 months), and to be useful to other researchers and practitioners they should have:

• clearly stated objectives with pre-defined eligibility criteria for studies
• explicit, reproducible methodology
• a systematic search that attempts to identify all studies
• assessment of the validity of the findings of the included studies (e.g. risk of bias)
• systematic presentation, and synthesis, of the characteristics and findings of the included studies

Not all systematic reviews contain meta-analysis. 

Meta-analysis is the use of statistical methods to summarize the results of independent studies. By combining information from all relevant studies, meta-analysis can provide more precise estimates of the effects of health care than those derived from the individual studies included within a review.  More information on meta-analyses can be found in  Cochrane Handbook, Chapter 9 .

A meta-analysis goes beyond critique and integration and conducts secondary statistical analysis on the outcomes of similar studies.  It is a systematic review that uses quantitative methods to synthesize and summarize the results.

An advantage of a meta-analysis is the ability to be completely objective in evaluating research findings.  Not all topics, however, have sufficient research evidence to allow a meta-analysis to be conducted.  In that case, an integrative review is an appropriate strategy. 

Some of the content in this section is from Systematic reviews and meta-analyses: step by step guide created by Kate McAllister.

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Research Methods and Design

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Literature Review

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A literature review is a discussion of the literature (aka. the "research" or "scholarship") surrounding a certain topic. A good literature review doesn't simply summarize the existing material, but provides thoughtful synthesis and analysis. The purpose of a literature review is to orient your own work within an existing body of knowledge. A literature review may be written as a standalone piece or be included in a larger body of work.

You can read more about literature reviews, what they entail, and how to write one, using the resources below. 

Am I the only one struggling to write a literature review?

Dr. Zina O'Leary explains the misconceptions and struggles students often have with writing a literature review. She also provides step-by-step guidance on writing a persuasive literature review.

An Introduction to Literature Reviews

Dr. Eric Jensen, Professor of Sociology at the University of Warwick, and Dr. Charles Laurie, Director of Research at Verisk Maplecroft, explain how to write a literature review, and why researchers need to do so. Literature reviews can be stand-alone research or part of a larger project. They communicate the state of academic knowledge on a given topic, specifically detailing what is still unknown.

This is the first video in a whole series about literature reviews. You can find the rest of the series in our SAGE database, Research Methods:

Videos covering research methods and statistics

Identify Themes and Gaps in Literature (with real examples) | Scribbr

Finding connections between sources is key to organizing the arguments and structure of a good literature review. In this video, you'll learn how to identify themes, debates, and gaps between sources, using examples from real papers.

4 Tips for Writing a Literature Review's Intro, Body, and Conclusion | Scribbr

While each review will be unique in its structure--based on both the existing body of both literature and the overall goals of your own paper, dissertation, or research--this video from Scribbr does a good job simplifying the goals of writing a literature review for those who are new to the process. In this video, you’ll learn what to include in each section, as well as 4 tips for the main body illustrated with an example.

• Literature Review This chapter in SAGE's Encyclopedia of Research Design describes the types of literature reviews and scientific standards for conducting literature reviews.
• UNC Writing Center: Literature Reviews This handout from the Writing Center at UNC will explain what literature reviews are and offer insights into the form and construction of literature reviews in the humanities, social sciences, and sciences.
• Purdue OWL: Writing a Literature Review The overview of literature reviews comes from Purdue's Online Writing Lab. It explains the basic why, what, and how of writing a literature review.

Organizational Tools for Literature Reviews

One of the most daunting aspects of writing a literature review is organizing your research. There are a variety of strategies that you can use to help you in this task. We've highlighted just a few ways writers keep track of all that information! You can use a combination of these tools or come up with your own organizational process. The key is choosing something that works with your own learning style.

Citation Managers

Citation managers are great tools, in general, for organizing research, but can be especially helpful when writing a literature review. You can keep all of your research in one place, take notes, and organize your materials into different folders or categories. Read more about citations managers here:

• Manage Citations & Sources

Concept Mapping

Some writers use concept mapping (sometimes called flow or bubble charts or "mind maps") to help them visualize the ways in which the research they found connects.

There is no right or wrong way to make a concept map. There are a variety of online tools that can help you create a concept map or you can simply put pen to paper. To read more about concept mapping, take a look at the following help guides:

• Using Concept Maps From Williams College's guide, Literature Review: A Self-guided Tutorial

Synthesis Matrix

A synthesis matrix is is a chart you can use to help you organize your research into thematic categories. By organizing your research into a matrix, like the examples below, can help you visualize the ways in which your sources connect. 

• Walden University Writing Center: Literature Review Matrix Find a variety of literature review matrix examples and templates from Walden University.
• Writing A Literature Review and Using a Synthesis Matrix An example synthesis matrix created by NC State University Writing and Speaking Tutorial Service Tutors. If you would like a copy of this synthesis matrix in a different format, like a Word document, please ask a librarian. CC-BY-SA 3.0
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• Next: Quantitative Research Methods >>
• Last Updated: Feb 6, 2024 9:20 AM

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Chapter Four: Theory, Methodologies, Methods, and Evidence

Research Methods

You are viewing the first edition of this textbook. a second edition is available – please visit the latest edition for updated information..

This page discusses the following topics:

Research Goals

Research method types.

Before discussing research   methods , we need to distinguish them from  methodologies  and  research skills . Methodologies, linked to literary theories, are tools and lines of investigation: sets of practices and propositions about texts and the world. Researchers using Marxist literary criticism will adopt methodologies that look to material forces like labor, ownership, and technology to understand literature and its relationship to the world. They will also seek to understand authors not as inspired geniuses but as people whose lives and work are shaped by social forces.

Example: Critical Race Theory Methodologies

Critical Race Theory may use a variety of methodologies, including

• Interest convergence: investigating whether marginalized groups only achieve progress when dominant groups benefit as well
• Intersectional theory: investigating how multiple factors of advantage and disadvantage around race, gender, ethnicity, religion, etc. operate together in complex ways
• Radical critique of the law: investigating how the law has historically been used to marginalize particular groups, such as black people, while recognizing that legal efforts are important to achieve emancipation and civil rights
• Social constructivism: investigating how race is socially constructed (rather than biologically grounded)
• Standpoint epistemology: investigating how knowledge relates to social position
• Structural determinism: investigating how structures of thought and of organizations determine social outcomes

To identify appropriate methodologies, you will need to research your chosen theory and gather what methodologies are associated with it. For the most part, we can’t assume that there are “one size fits all” methodologies.

Research skills are about how you handle materials such as library search engines, citation management programs, special collections materials, and so on.

Research methods  are about where and how you get answers to your research questions. Are you conducting interviews? Visiting archives? Doing close readings? Reviewing scholarship? You will need to choose which methods are most appropriate to use in your research and you need to gain some knowledge about how to use these methods. In other words, you need to do some research into research methods!

Your choice of research method depends on the kind of questions you are asking. For example, if you want to understand how an author progressed through several drafts to arrive at a final manuscript, you may need to do archival research. If you want to understand why a particular literary work became a bestseller, you may need to do audience research. If you want to know why a contemporary author wrote a particular work, you may need to do interviews. Usually literary research involves a combination of methods such as  archival research ,  discourse analysis , and  qualitative research  methods.

Literary research methods tend to differ from research methods in the hard sciences (such as physics and chemistry). Science research must present results that are reproducible, while literary research rarely does (though it must still present evidence for its claims). Literary research often deals with questions of meaning, social conventions, representations of lived experience, and aesthetic effects; these are questions that reward dialogue and different perspectives rather than one great experiment that settles the issue. In literary research, we might get many valuable answers even though they are quite different from one another. Also in literary research, we usually have some room to speculate about answers, but our claims have to be plausible (believable) and our argument comprehensive (meaning we don’t overlook evidence that would alter our argument significantly if it were known).

A literary researcher might select the following:

Theory: Critical Race Theory

Methodology: Social Constructivism

Method: Scholarly

Skills: Search engines, citation management

Wendy Belcher, in  Writing Your Journal Article in 12 Weeks , identifies two main approaches to understanding literary works: looking at a text by itself (associated with New Criticism ) and looking at texts as they connect to society (associated with Cultural Studies ). The goal of New Criticism is to bring the reader further into the text. The goal of Cultural Studies is to bring the reader into the network of discourses that surround and pass through the text. Other approaches, such as Ecocriticism, relate literary texts to the Sciences (as well as to the Humanities).

The New Critics, starting in the 1940s,  focused on meaning within the text itself, using a method they called “ close reading .” The text itself becomes e vidence for a particular reading. Using this approach, you should summarize the literary work briefly and q uote particularly meaningful passages, being sure to introduce quotes and then interpret them (never let them stand alone). Make connections within the work; a sk  “why” and “how” the various parts of the text relate to each other.

Cultural Studies critics see all texts  as connected to society; the critic  therefore has to connect a text to at least one political or social issue. How and why does  the text reproduce particular knowledge systems (known as discourses) and how do these knowledge systems relate to issues of power within the society? Who speaks and when? Answering these questions helps your reader understand the text in context. Cultural contexts can include the treatment of gender (Feminist, Queer), class (Marxist), nationality, race, religion, or any other area of human society.

Other approaches, such as psychoanalytic literary criticism , look at literary texts to better understand human psychology. A psychoanalytic reading can focus on a character, the author, the reader, or on society in general. Ecocriticism  look at human understandings of nature in literary texts.

We select our research methods based on the kinds of things we want to know. For example, we may be studying the relationship between literature and society, between author and text, or the status of a work in the literary canon. We may want to know about a work’s form, genre, or thematics. We may want to know about the audience’s reading and reception, or about methods for teaching literature in schools.

Below are a few research methods and their descriptions. You may need to consult with your instructor about which ones are most appropriate for your project. The first list covers methods most students use in their work. The second list covers methods more commonly used by advanced researchers. Even if you will not be using methods from this second list in your research project, you may read about these research methods in the scholarship you find.

Most commonly used undergraduate research methods:

• Scholarship Methods:  Studies the body of scholarship written about a particular author, literary work, historical period, literary movement, genre, theme, theory, or method.
• Textual Analysis Methods:  Used for close readings of literary texts, these methods also rely on literary theory and background information to support the reading.
• Biographical Methods:  Used to study the life of the author to better understand their work and times, these methods involve reading biographies and autobiographies about the author, and may also include research into private papers, correspondence, and interviews.
• Discourse Analysis Methods:  Studies language patterns to reveal ideology and social relations of power. This research involves the study of institutions, social groups, and social movements to understand how people in various settings use language to represent the world to themselves and others. Literary works may present complex mixtures of discourses which the characters (and readers) have to navigate.
• Creative Writing Methods:  A literary re-working of another literary text, creative writing research is used to better understand a literary work by investigating its language, formal structures, composition methods, themes, and so on. For instance, a creative research project may retell a story from a minor character’s perspective to reveal an alternative reading of events. To qualify as research, a creative research project is usually combined with a piece of theoretical writing that explains and justifies the work.

Methods used more often by advanced researchers:

• Archival Methods: Usually involves trips to special collections where original papers are kept. In these archives are many unpublished materials such as diaries, letters, photographs, ledgers, and so on. These materials can offer us invaluable insight into the life of an author, the development of a literary work, or the society in which the author lived. There are at least three major archives of James Baldwin’s papers: The Smithsonian , Yale , and The New York Public Library . Descriptions of such materials are often available online, but the materials themselves are typically stored in boxes at the archive.
• Computational Methods:  Used for statistical analysis of texts such as studies of the popularity and meaning of particular words in literature over time.
• Ethnographic Methods:  Studies groups of people and their interactions with literary works, for instance in educational institutions, in reading groups (such as book clubs), and in fan networks. This approach may involve interviews and visits to places (including online communities) where people interact with literary works. Note: before you begin such work, you must have  Institutional Review Board (IRB)  approval “to protect the rights and welfare of human participants involved in research.”
• Visual Methods:  Studies the visual qualities of literary works. Some literary works, such as illuminated manuscripts, children’s literature, and graphic novels, present a complex interplay of text and image. Even works without illustrations can be studied for their use of typography, layout, and other visual features.

Regardless of the method(s) you choose, you will need to learn how to apply them to your work and how to carry them out successfully. For example, you should know that many archives do not allow you to bring pens (you can use pencils) and you may not be allowed to bring bags into the archives. You will need to keep a record of which documents you consult and their location (box number, etc.) in the archives. If you are unsure how to use a particular method, please consult a book about it. [1] Also, ask for the advice of trained researchers such as your instructor or a research librarian.

• What research method(s) will you be using for your paper? Why did you make this method selection over other methods? If you haven’t made a selection yet, which methods are you considering?
• What specific methodological approaches are you most interested in exploring in relation to the chosen literary work?
• What is your plan for researching your method(s) and its major approaches?
• What was the most important lesson you learned from this page? What point was confusing or difficult to understand?

Write your answers in a webcourse discussion page.

• Introduction to Research Methods: A Practical Guide for Anyone Undertaking a Research Project  by Catherine, Dr. Dawson
• Practical Research Methods: A User-Friendly Guide to Mastering Research Techniques and Projects  by Catherine Dawson
• Qualitative Inquiry and Research Design: Choosing Among Five Approaches  by John W. Creswell  Cheryl N. Poth
• Qualitative Research Evaluation Methods: Integrating Theory and Practice  by Michael Quinn Patton
• Research Design: Qualitative, Quantitative, and Mixed Methods Approaches  by John W. Creswell  J. David Creswell
• Research Methodology: A Step-by-Step Guide for Beginners  by Ranjit Kumar
• Research Methodology: Methods and Techniques  by C.R. Kothari

Strategies for Conducting Literary Research Copyright © 2021 by Barry Mauer & John Venecek is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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• Published: 25 April 2024

A scoping review of academic and grey literature on migrant health research conducted in Scotland

• G. Petrie 1 ,
• K. Angus 2 &
• R. O’Donnell 2  

BMC Public Health volume  24 , Article number:  1156 ( 2024 ) Cite this article

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Migration to Scotland has increased since 2002 with an increase in European residents and participation in the Asylum dispersal scheme. Scotland has become more ethnically diverse, and 10% of the current population were born abroad. Migration and ethnicity are determinants of health, and information on the health status of migrants to Scotland and their access to and barriers to care facilitates the planning and delivery of equitable health services. This study aimed to scope existing peer-reviewed research and grey literature to identify gaps in evidence regarding the health of migrants in Scotland.

A scoping review on the health of migrants in Scotland was carried out for dates January 2002 to March 2023, inclusive of peer-reviewed journals and grey literature. CINAHL/ Web of Science/SocIndex and Medline databases were systematically searched along with government and third-sector websites. The searches identified 2166 journal articles and 170 grey literature documents for screening. Included articles were categorised according to the World Health Organisation’s 2016 Strategy and Action Plan for Refugee and Migrant Health in the European region. This approach builds on a previously published literature review on Migrant Health in the Republic of Ireland.

Seventy-one peer reviewed journal articles and 29 grey literature documents were included in the review. 66% were carried out from 2013 onwards and the majority focused on asylum seekers or unspecified migrant groups. Most research identified was on the World Health Organisation’s strategic areas of right to health of refugees, social determinants of health and public health planning and strengthening health systems. There were fewer studies on the strategic areas of frameworks for collaborative action, preventing communicable disease, preventing non-communicable disease, health screening and assessment and improving health information and communication.

While research on migrant health in Scotland has increased in recent years significant gaps remain. Future priorities should include studies of undocumented migrants, migrant workers, and additional research is required on the issue of improving health information and communication.

Peer Review reports

The term migrant is defined by the International Organisation for Migration as “ a person who moves away from his or her place of usual residence, whether within a country or across an international border, temporarily or permanently, and for a variety of reasons. The term includes several well-defined legal categories of people, including migrant workers; persons whose particular types of movements are legally-defined, such as smuggled migrants; as well as those whose status are not specifically defined under international law, such as international students.” [ 1 ] Internationally there are an estimated 281 million migrants – 3.6% of the world population, including 26.4 million refugees and 4.1 million asylum seekers – the highest number ever recorded [ 2 ]. The UN Refugee Society defines the term refugee as “ someone who has been forced to flee his or her country because of persecution, war or violence…most likely, they cannot return home or are afraid to do so .” The term asylum-seeker is defined as “someone whose request for sanctuary has yet to be processed.” [ 3 ].

Net-migration to Europe was negative in the 19th century due to higher levels of emigration, however in the mid-20th century immigration began to rise, because of an increase in migrant workers and following conflicts in the Middle East and North Africa [ 4 ]. Current migration drivers include conflicts alongside world-wide economic instability, exacerbated by the Covid-19 pandemic [ 5 ]. Environmental damage due to climate change is expected to inflate the number of asylum seekers entering Europe in future [ 6 ]. The increase in migration to Europe is not a short-term influx but a long-term phenomenon, and European nations must adapt and find solutions to resulting financial, safeguarding and health challenges [ 7 ].

Data on healthcare use by migrants in Europe is variable, which means cross-country comparisons are inadequate [ 8 ]. Many countries do not record migration information within health records and all use disparate criteria to classify migrant status. The lack of comparative data hinders public health surveillance and effective interventions [ 9 ]. Even where information is available, results can be contradictory due to the multifarious migrant population. Migrants have a wide range of origin countries, socio-economic position, age and journeys undertaken which can affect health status [ 10 ].

Migrants initially may have better health than the general population, known as the ‘Healthy Migrant effect’ [ 11 ]. However, health declines with increasing length of residence [ 12 ] and over time to levels comparable with the general population [ 13 ]. Second generation immigrants may have higher mortality than average [ 14 ]. The process of acculturation to the host country, with adoption of unhealthy lifestyle and behaviours, increases the risk for chronic disease [ 15 ]. In addition, inequalities in health of migrants compared to host populations has been confirmed by wide-ranging research [ 16 ].

Host countries may limit healthcare access, with undocumented migrants sometimes only entitled to emergency care [ 17 ]. Even when access is granted, inequitable services can affect quality of care due to language barriers and cultural factors [ 18 ]. Poor working/living conditions and discrimination can exacerbate health inequalities [ 12 ]. Processing facilities for asylum seekers are frequently overpopulated, stressful environments [ 19 ] and threat of deportation, lack of citizenship rights and integration can negatively affect health and access to care [ 20 ]. Undocumented workers are unprotected by health and safety legislation leading to dangerous working conditions and injuries [ 15 ].

A systematic review of migrant health in the European Union (EU) found migrants have worse self-perceived health than the general population [ 21 ]. Research evidence indicates increased prevalence of cardiovascular disease, diabetes, mental health disorders and adverse pregnancy outcomes. Exposure to conflict, harsh travel conditions and suboptimal vaccine programmes can mean higher risk of communicable disease [ 22 ]. Scoping reviews have also been conducted to describe trends within migration health research in the United Kingdom (UK) [ 23 ] and identify gaps for future research agendas in the UK [ 23 ] and in the Republic of Ireland [ 24 ].

Almost three-quarters (73%) of published migration health research in the UK has been conducted in England, focusing primarily on infectious diseases and mental health. There is limited evidence on the social determinants of health, access to and use of healthcare and structural and behavioural factors behaviours that influence migrant health in the UK [ 23 ]. By contrast, a large amount of the migration research conducted in the Republic of Ireland has focused on the social determinants of health, and on health system adaptations, with a paucity of research focusing on improving health information systems [ 24 ].

Migration and Health in Scotland

Immigration to Scotland began to rise in 2003 with the expansion of the EU [ 25 ]. The population in Scotland increased from 5.11 million to 5.47 million between 2005 and 2020 and is predicted to continue rising until 2028 [ 26 ] despite low birth rates, with the increased population resulting from inward migration [ 27 ]. Scotland’s population is becoming more ethnically diverse [ 28 ] and susceptibility to different health conditions varies by ethnic group, which has implications for the planning and provision of health services [ 29 ]. 7% of the current Scottish population are non-UK nationals and 10% were born outside Britain. The commonest countries of origin were Poland, Ireland, Italy, Nigeria and India [ 30 ].

Within Scotland, linking health data to ethnicity is standard in order to monitor and improve health of minority groups [ 31 ]. Ethnic background can differ from country of birth which means migration status cannot be assumed [ 32 ], although health inequalities experienced by migrants often extend to affect all ethnic minority groups [ 33 ]. The Scottish Health and Ethnicity Linkage Study (SHELS) linked census data to health records of 91% of the population which has provided information on mortality and morbidity by ethnic group and country of birth [ 34 ]. SHELS research indicates that the white-Scottish population have a higher mortality rate than other ethnic groups. This may be consequent to the comparatively poor health of the Scottish population relative to other European nations: high mortality rates in the general population may cause a perception that the health of minorities is more advantageous than in reality [ 35 ].

Cezard et al’s [ 13 ] analysis of self-perceived health among people in Scotland found that being born abroad had a positive impact on health status. Health declined with increased length of residence, which may be explained by cultural convergence with the majority population. Allik et al. [ 36 ] compared health inequalities by ethnic background and found that with increasing age, health differences reduced thus people aged over 75 of all ethnicities had similar or worse health status than White-Scottish people. While working-age migrants appear to be healthier than the White Scottish population, it cannot be assumed that in future this would extend to older age groups.

Research has shown deprivation as a cause of heath inequalities among ethnic minority and migrant groups [ 37 ]. The socio-economic status of minority ethnic groups in Scotland is unusual, as most are of similar or higher status than the white-Scottish population [ 38 ]. Therefore, public health interventions targeting deprivation may not address risk-factors for ethnic minorities and migrants [ 36 ]. Further research on determinants of health in migrants can help with planning and design of inclusive policies.

The 2011 census indicated that 50% of immigrants lived in the cities of Edinburgh, Glasgow, and Aberdeen. Glasgow had a greater percentage of non-European immigrants due to participation in the Asylum dispersal programme [ 39 ]. 10% of UK asylum seekers are placed in Glasgow, but records are not kept following approval of asylum claims, therefore the size of the refugee population is unknown [ 40 ]. While immigration is controlled by the British government, in policy areas devolved to the Scottish government, refugees and asylum seekers have more rights than elsewhere in UK, including access to primary healthcare for undocumented migrants [ 40 ]. Despite the mitigating effect of Scottish policies, asylum seekers’ health is worsened by the asylum process and associated poverty, marginalisation, and discrimination [ 40 ]. Health deteriorates with increasing length of time in the asylum system [ 40 ] and asylum seekers and refugees have additional health needs and require enhanced support [ 41 ]. Research on the health needs of asylum seekers in Scotland is required to ensure adequate healthcare.

Aim and objectives

While scoping reviews on migrant health have been carried out in Europe [ 12 ], Ireland [ 24 ] and the UK [ 23 ] none are currently specific to the Scottish context. Given the devolved government of Scotland and demographics described above, a targeted review would help to clarify research priorities, with the aim of improving health and health care within the migrant community in Scotland. This work therefore builds on the published scoping review of migrant health in the Republic of Ireland [ 24 ]. The authors recommend replication of the study in other countries to facilitate cross-country comparison. Our aim was to scope peer-reviewed research and grey literature on migrant health conducted in Scotland and identify any gaps in the evidence. Our objectives were to: [1] understand the extent of the available research by topic area [2] summarise the types of research already conducted, populations studied, topics covered and approaches taken [3], map the existing research conducted in Scotland and [4] identify areas for future research based on any gaps in the evidence identified.

A scoping review was conducted as they can aid detection of evidence gaps [ 42 ] and allow incorporation of grey literature in topics with insufficient published research [ 43 ]. Arksey and O’Malley’s [ 44 ] five stage scoping review framework was used.

Stage 1: identifying the research question

Arskey and O’Malley [ 44 ] suggest maintaining a broad approach to identifying the research question, in order to generate breadth of coverage. On this basis, and in line with the research question identified in the Villarroel et al. [ 24 ] scoping review, our research question was framed as follows: What is the scope, main topics and gaps in evidence in the existing literature on health of international migrants living in Scotland? Arksey and O’Malley [ 44 ] highlight the importance of defining terminology at the outset of scoping reviews. For consistency, we used the broad definition of ‘migrant’ as per Villaroel et al. [ 24 ], from the International Organisation for Migration (IOM) [ 1 ]. References to refugees or asylum seekers followed the United Nations Refugee Agency definitions [ 3 ].

Stage 2: identifying relevant studies

Electronic database searches identified reports alongside a grey literature search, in line with Arskey and O’Malley’s [ 44 ] guidance to search for evidence via different sources. CINAHL, Web of Science, SocIndex and Medline academic databases were selected with input from co-authors. Search terms for the review were based upon those used by Villaroel et al. [ 24 ] with additional relevant terms from Hannigan et al. [ 9 ] The strategy combined three sets of terms for: Migrants (e.g., refugee, migrant, immigrant or newcomer), Scotland and Health. Both free text terms and index terms were used and adapted to the 4 academic databases and searches were run on 10th March 2023 (see Additional File 1 for database search strategies). Thirteen Government, University, and third-sector websites in Scotland were scoped for selection then hand-searched for grey literature (listed in Additional File 1 ).

Stage 3: study selection

Net-migration to Scotland increased in the 2000s [ 27 ] hence a date range of January 2002-March 2023 was used to identify evidence. The search was limited to English only. Inclusion/exclusion criteria for the studies were based on those used by Villaroel et al. [ 24 ] and expanded upon following discussion with co-authors (see Table  1 ). Reports were included if based on primary or secondary research on the health of international migrants in Scotland and used qualitative, quantitative or mixed methods research design. International or UK based reports were only included if Scottish results were documented separately. Reports on the health of ethnic minority groups in Scotland was included if place of birth was recorded. Research on internal (non-international) migrants within Scotland, either moving from one Scottish area to another or from another part of the United Kingdom to Scotland, were excluded.

Stage 4: data charting

All records were saved to RefWorks for screening. Records were first screened at title/abstract stage with 10% independently checked by the co-authors. The remaining reports were single screened using full text by the first author. Data from the included records was extracted and organised in tabular form under the following headings, which were agreed by team members: article type (peer-reviewed article or grey literature), publication date, geographical setting, study/intervention’s target population, funding, primary research focus on migrant health (y/n), study objective, data collection method, study design (qualitative/quantitative/mixed) and main finding. Reports were not critically appraised in this scoping review.

Stage 5: collating, summarising and reporting results

A report (either a peer-reviewed journal article or grey literature report) is used as our unit of analysis. In order to present the range of research identified, reports were grouped by the different headings in our data charting table and the outcomes considered for relevance to our scoping review’s aim. Our Results summarise the recency, focus, study designs and funding sources of the identified research, followed by the geographical settings and whether Scotland was included in international research reports. Reports were grouped by their study population and further sub-divided by publication type and geographical area for summarising. Finally, the WHO’s European strategy and action plan (SAAP) for refugee and migrant health [ 7 ] is a policy framework designed to help governments and other stakeholders monitor and improve migrant health in Europe. There are nine strategic areas in the WHO’s SAAP, which prioritise the most salient issues. In line with Villaroel et al’s [ 24 ] approach and in order to compare scoping review outcomes, these areas were used to categorise the findings of this review. Each report was matched to the most appropriate SAAP:

Establishing a Framework for Collaborative Action.

Advocating for the right to health of refugees.

Addressing the social determinants of health.

Achieving public health preparedness and ensuring an effective response.

Strengthening health systems and their resilience.

Preventing communicable disease.

Preventing and reducing the risks caused by non-communicable disease.

Ensuring ethical and effective health screening and assessment.

Improving health information and communication.

The primary focus (aims and objectives) of each report was used to identify the relevant SAAP area/areas. To improve reliability, results were compared using coding criteria used in Villaroel et al’s study (MacFarlane 2023, personal communication, 31st May). 10% of the reports were checked by one co-author to ensure consistent coding to SAAP categories. Any instances of uncertainty in mapping reports to the relevant SAAP area/areas were discussed and resolved by team members.

This scoping review of the literature on migrant health in Scotland identified 2166 records from academic literature databases, following duplicate removal, and 170 records from website searches (see Fig.  1 ). Following screening, a total of 71 peer-reviewed journal articles and 29 grey literature studies (totalling 100 reports) were included for analysis (Results table and reference list are presented in Additional File 2 ).

Flow chart illustrating the identification of sources of evidence included in the scoping review

Overall findings

The majority of reports were published between 2013 and 2022. Fifty-eight reports (58%) focused exclusively on migrant health [ 18 , 39 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 ]. 23 centred on health but included other populations in addition to migrants – for example research on ethnic minorities or other vulnerable groups [ 13 , 31 , 35 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 ]. Seventeen reports were included where the sample population were migrants, but the primary topic was not health – for example destitution, integration, and service needs [ 27 , 73 , 74 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 ]. Health data was reported as part of the wider subject matter. One report [ 136 ] looked at the social determinants of breastfeeding including migrant status and one [ 137 ] compared attitudes to aging and family support between countries.

Funding sources were not declared for 35 (35%) of reports. The Scottish Government funded 20 reports (20%) [ 13 , 27 , 32 , 39 , 45 , 46 , 47 , 66 , 77 , 88 , 99 , 100 , 101 , 102 , 113 , 116 , 119 , 121 , 129 , 134 ]. Other common sources of funding included Government funded public bodies ( n  = 13) [ 45 , 48 , 49 , 50 , 51 , 52 , 53 , 104 , 107 , 113 , 116 , 131 , 136 ], the Scottish Health Service ( n  = 18) (either the National Health Service (NHS) [ 13 , 54 , 56 , 57 , 58 , 59 , 102 , 113 , 116 ], local NHS trusts [ 45 , 60 , 61 , 77 , 102 , 103 , 112 ] or by Public Health Scotland [ 13 , 113 ]) Eleven reports (11%) were funded by Universities. The charity sector financed 15 (15%) reports [ 53 , 63 , 66 , 69 , 70 , 71 , 72 , 73 , 74 , 103 , 111 , 123 , 125 , 132 , 138 ] and the EU and Scottish local authorities funded four reports each [ 45 , 62 , 75 , 76 , 77 , 102 , 125 , 135 ]. Professional bodies financed one report [ 126 ] as did the Japanese government [ 64 ]. No reports received funding from the business sector. The biggest sources of funding for grey literature were Refugee charities (40%) and the Scottish government (30%) (see Fig. 2 ).

Sources of funding for migrant health research in Scotland

Research methods and data collection

52% of reports used qualitative research methods. Forty-five reports (86%) collected data using 1–1 interviews and 24 (46%) used focus groups. Other methods of data collection included questionnaires (six studies (11%)), workshops (two studies (3.85%)) and observation (two studies (3.85%)). Oral/written evidence, guided play sessions, family case studies and participatory activity sessions were used in one report each.

28% of reports used quantitative research methods, most commonly cross section design (ten studies (36%)) and cohort design (18 studies (64%)). Information was obtained from databases including medical records, Census data and national records in 21 reports (75%). Questionnaires were used in six reports (21%). Other methods including body measurements, food diaries, blood samples, interviews and case reviews were used in 1 report each.

20% of reports used mixed methods. The most common method of data collection was questionnaires in 14 reports (70%), interviews in ten reports (50%), focus groups in seven reports (35%), workshops in three reports (13.6%), and databases in three reports (13.6%). Other methods included literature review in two reports (10%), case note reviews in two reports (10%) and one reports each used mapping and school records.

Geographical areas of study

Ninety-one reports were situated in Scotland, of which 35 (38.5%) covered the whole country and 56 (61.5%) specified a city or area where research was undertaken. Some UK and international reports also specified the area of Scotland. The largest share of research within Scotland overall was in Glasgow with 36 reports, followed by Edinburgh with 16 reports, Lothian with six reports, Aberdeen with five reports and Grampian with three reports. The Northeast, Stirling, Highlands, Inverness, Lanarkshire, Motherwell and Selkirk had one report in each area.

There were seven international reports, three on mortality by country of birth [ 75 , 76 , 78 ], one on cross cultural communication [ 79 ], one on maternity care in Poland and Scotland [ 99 ], one comparing attitudes to aging in China and Scotland [ 137 ] and one on the link between birthweights and integration of migrants [ 64 ]. The remaining two reports were UK based, one on immunisation of Roma and traveller communities [ 117 ] and one on the link between ethnic diversity and mortality [ 104 ]. All the included international and UK reports documented the Scottish data separately within results.

Migrant population

Thirty-one reports included all migrants in the study population. The remaining reports included 30 studies on asylum seekers/refugees, 11 on Polish migrants, ten on Africans, six each on South Asians/Chinese/European, three on Arabs, and two on Roma populations (see Fig.  3 ). Most reports did not specify the country of origin for Asylum seekers and refugees - where country of birth was specified, reports were also included in the appropriate category.

Migrant populations studied in health research in Scotland

Grey literature and peer-reviewed reports differed in population focus. The most common populations of interest in grey literature were asylum seekers/refugees consisting of 18 reports (62%) [ 27 , 47 , 54 , 55 , 59 , 63 , 70 , 71 , 72 , 73 , 74 , 123 , 125 , 127 , 128 , 132 , 134 , 138 ] while for peer-reviewed journals 24 reports (34%) focused on all migrants [ 13 , 35 , 45 , 48 , 64 , 76 , 78 , 79 , 80 , 81 , 104 , 105 , 108 , 109 , 113 , 114 , 115 , 116 , 118 , 120 , 121 , 122 , 136 ].

Migrant study population also differed by local area; Glasgow city, where the majority of research occurred, had 18 reports of 36 (50%) on Asylum seekers/refugees [ 47 , 48 , 52 , 53 , 54 , 55 , 58 , 63 , 70 , 71 , 72 , 82 , 83 , 127 , 128 , 130 , 138 , 139 ] eight reports (22%) on Africans [ 52 , 53 , 84 , 85 , 86 , 87 , 106 , 107 ], seven reports (19%) on all migrants [ 45 , 48 , 80 , 102 , 104 , 105 , 121 ] and two reports (5.5%) on Roma migrants [ 103 , 117 ]. Other populations had one reports each. In Edinburgh five reports of 16 (31%) were on the Polish population [ 56 , 67 , 68 , 89 , 90 ], and two reports (12.5%) on Asylum seekers/refugees [ 60 , 133 ], Chinese [ 62 , 137 ], South Asian [ 46 , 119 ], all migrants [ 105 , 121 ] and Africans [ 87 , 107 ]. The remaining migrant groups had one report each. Other areas of Scotland show no clear pattern with studies in disparate migrant population groups.

Number of reports per Strategic and Action Plan (SAAP) Area

SAAP Area mapping

1. establishing a framework for collaborative action.

Nine reports had a primary focus on collaborative action and were categorised under SAAP area 1 (see Fig.  4 ) [ 66 , 70 , 72 , 73 , 103 , 125 , 129 , 132 , 134 ]. Four reports (33%) used a mixed methods study design, the remaining five reports (67%) used a qualitative design. One report [ 66 ] focused on the epidemiology of female genital mutilation and a proposed intervention strategy. One report [ 66 ] focused on the epidemiology of female genital mutilation and a proposed intervention strategy. One report [ 103 ] evaluated service provision to the Roma community in Glasgow. The remaining reports focused on refugees and asylum seekers: four [ 73 , 125 , 132 , 134 ] evaluations of refugee integration projects, one [ 70 ] on services available to pregnant women, and one [ 72 ] an assessment of a peer-education service. One report [ 129 ] was a review of service provisions for migrants during the Covid-19 pandemic. All reports in SAAP area 1 were grey literature and three (37.5%) had a primary focus on migrant health while four (50%) focused on integration, one (11%) included data on ethnic minorities and one (11%) on services during the covid-19 pandemic. The majority (seven reports (78%)) were also categorised to another SAAP area most commonly area 2 (five studies (55%)) or area 5 (four studies (44%)).

2. Advocating for the right to health of refugees

Nineteen reports focused on SAAP area 2, advocating for the right to health of refugees (see Fig.  4 ) [ 47 , 52 , 53 , 54 , 55 , 63 , 70 , 71 , 83 , 103 , 123 , 124 , 125 , 127 , 128 , 129 , 134 , 138 , 140 ]. Sixteen reports (84%) had a qualitative study design and the remaining three (16%) reports used mixed methods. Nine reports (47%) focused on the health impact of the asylum system [ 52 , 55 , 71 , 74 , 123 , 127 , 128 , 129 , 138 ], five (26%) on health and access to care [ 47 , 54 , 83 , 103 , 124 ], two (10.5%) on maternity care [ 63 , 70 ], two (10.5%) on integration services [ 125 , 134 ] and one report on mental health in HIV positive migrants [ 53 ]. Nine reports (47%) had a primary focus on migrant health while the remaining 10 (53%) also involved wider social issues. The majority (15 (79%)) of reports were grey literature. All the articles in this group overlapped with another SAAP area. Area 3 is the most common joint category with ten reports (53%) followed by area 5 with seven reports (37%), area 1 shares five reports (26%), while areas 4 and 8 share one report each (5%).

3. Addressing the social determinants of health

Twenty-nine reports were categorised to SAAP area 3 – addressing the social determinants of health (see Fig.  4 ) [ 13 , 27 , 45 , 50 , 52 , 55 , 60 , 62 , 63 , 65 , 68 , 71 , 74 , 80 , 81 , 82 , 91 , 92 , 93 , 102 , 112 , 123 , 124 , 127 , 128 , 136 , 137 , 138 ]. The majority (14 (48%)) used a qualitative study method, eight (28%) used quantitative methodology and the remaining seven reports (24%) used mixed methods. Nineteen reports (65.5%) were peer-reviewed journals [ 13 , 45 , 50 , 52 , 60 , 62 , 63 , 65 , 68 , 80 , 81 , 82 , 91 , 92 , 93 , 104 , 112 , 124 , 136 , 137 ] and ten (34.5%) were grey literature [ 27 , 55 , 63 , 71 , 74 , 102 , 123 , 127 , 128 , 138 ]. Ten reports (34.5%) discussed the effects of the asylum system on health [ 27 , 52 , 63 , 71 , 74 , 123 , 124 , 127 , 128 , 137 ] and one (3.5%) migration and health [ 50 ]. Six reports (21%) focused on culture and ethnicity [ 82 , 92 , 102 , 104 , 112 , 137 ], five reports (17%) discussed economic and environmental determinants of health [ 13 , 45 , 67 , 81 , 93 ] and five reports (17%) the health impact of social activities [ 55 , 60 , 62 , 80 , 91 ]. Of the remaining reports, one [ 65 ] discussed Brexit and mental health of European migrants and one discussed the effect of coping strategies on wellbeing in Polish migrants [ 68 ]. Most reports, 18 (62%) had a primary focus on migrant health [ 45 , 50 , 52 , 55 , 60 , 62 , 63 , 65 , 67 , 68 , 71 , 80 , 81 , 82 , 91 , 92 , 93 , 102 ], six reports (21%) discussed wider social factors in addition to health [ 74 , 123 , 124 , 127 , 128 , 138 ]. Of the remaining reports three (10%) looked at ethnic background and country of birth [ 13 , 112 , 136 ], one [ 27 ] included other vulnerable groups and one [ 137 ] included people living in China and Chinese migrants to Scotland. Thirteen reports were also categorised to one or more additional SAAP area - ten (34%) were also applicable to area 2 [ 52 , 55 , 63 , 71 , 74 , 123 , 124 , 127 , 128 , 138 ], three (10%) to area 5 [ 63 , 82 , 92 ] and one (7%) to area 4 [ 27 ].

4. Achieving public health preparedness and ensuring an effective response

Twenty-one reports were assigned to SAAP area 4 (see Fig.  4 ) [ 27 , 31 , 35 , 39 , 47 , 57 , 64 , 75 , 76 , 77 , 78 , 94 , 104 , 108 , 109 , 111 , 113 , 114 , 116 , 120 , 135 ] of which fourteen (67%) used quantitative research methods, four (19%) mixed methods and three (14%) qualitative methods. Thirteen (62%) reports were peer-reviewed journals [ 35 , 59 , 64 , 75 , 78 , 104 , 108 , 109 , 111 , 113 , 114 , 116 , 120 ] and eight (38%) grey literature [ 27 , 31 , 39 , 47 , 57 , 77 , 94 , 135 ]. Most reports (12 (57%)) focused on morbidity and mortality in migrant populations [ 31 , 35 , 64 , 75 , 76 , 78 , 104 , 108 , 109 , 113 , 114 , 116 ]. Six (29%) investigated health status and healthcare needs in migrant groups in Scotland [ 39 , 47 , 57 , 77 , 94 , 135 ]. Two reports (9.5%) analysed the epidemiology of HIV infections [ 111 , 120 ] and the remaining report focused on the health needs of young people during the covid-19 pandemic [ 27 ]. Nine reports (43%) had a primary focus on migrant health [ 39 , 47 , 55 , 64 , 75 , 76 , 77 , 78 , 94 ] while eight (38%) also analysed data by ethnicity [ 31 , 35 , 104 , 108 , 109 , 113 , 114 , 116 ]. Of the remaining reports, three (14%) included other populations within Scotland [ 27 , 111 , 120 ] and one (5%) included other characteristics in addition to health information [ 135 ]. Ten reports (48%) were also categorised to another SAAP area; one to area 2 [ 47 ], one to area 3 [ 27 ], four to area 5 [ 47 , 57 , 77 , 135 ], two to area 6 [ 111 , 120 ] and two to area 9 [ 31 , 108 ].

5. Strengthening health systems and their resilience

Twenty-nine reports were assigned to SAAP area 5 (see Fig.  4 ) [ 18 , 47 , 48 , 49 , 54 , 57 , 63 , 69 , 70 , 72 , 77 , 79 , 82 , 83 , 92 , 95 , 96 , 97 , 99 , 101 , 103 , 118 , 119 , 126 , 129 , 131 , 133 , 135 , 141 ] of which 23 (79%) used qualitative research methods. Three reports used quantitative methods (10.3%) and the remaining three used mixed methods (10.3%). Twelve reports (41%) examined migrants needs and experiences of health care [ 47 , 49 , 54 , 57 , 58 , 77 , 83 , 95 , 103 , 119 , 129 , 135 ], eight (24%) focused on pregnancy and childcare [ 63 , 70 , 92 , 96 , 97 , 99 , 101 , 118 ] and two (7%) on barriers to healthcare access [ 48 , 131 ]. Two reports (7%) evaluated healthcare programmes [ 72 , 133 ] and two focused on communication in primary care [ 79 ] and maternity services [ 69 ]. The remaining three reports (10%) covered sexual health [ 82 ], health information needs of Syrian refugees [ 126 ] and general practitioner training [ 18 ]. Nineteen (65.5%) were peer reviewed journals [ 18 , 48 , 49 , 58 , 69 , 79 , 82 , 83 , 92 , 95 , 96 , 97 , 99 , 101 , 118 , 119 , 125 , 131 , 133 ] and ten (34.5%) were grey literature [ 47 , 54 , 57 , 63 , 70 , 72 , 77 , 103 , 129 , 135 ]. Twenty-one (72%) had a primary focus on migrant health [ 18 , 47 , 48 , 49 , 54 , 57 , 58 , 63 , 69 , 70 , 72 , 77 , 79 , 82 , 83 , 92 , 95 , 96 , 97 , 99 , 101 ]. Six reports (21%) included research on other characteristics or services [ 103 , 126 , 129 , 131 , 133 , 135 ]. The remaining two reports (7%) included ethnic groups as well as migrants in the data [ 118 , 119 ]. Nineteen reports (65.5%) were also assigned to one or more other category areas: five reports (17%) to area 1 [ 47 , 70 , 72 , 103 , 129 ], five reports (17%) to area 2 [ 54 , 63 , 83 , 103 , 129 ], three reports (10%) to area 3 [ 63 , 82 , 92 ], four reports (14%) to area 4 [ 47 , 57 , 77 , 135 ], one (3.5%) to area 7 [ 119 ] and one (3.5%) to area 9 [ 48 ].

6. Preventing communicable diseases

Fourteen reports were assigned to SAAP area 6 (see Fig.  4 ) [ 56 , 61 , 87 , 88 , 89 , 90 , 105 , 106 , 107 , 111 , 115 , 117 , 120 , 122 ] of which four (31%) used quantitative methods, five (38%) used qualitative methods and five (38%) used mixed methods. Five reports (38.5%) examined immunisation behaviour [ 56 , 61 , 89 , 90 , 117 ], five (38%) on epidemiology and treatment of HIV [ 106 , 107 , 111 , 120 , 122 ]. The remaining four reports (31%) focused on tuberculosis in healthcare workers [ 115 ], malaria [ 105 ] and sexual health services [ 87 , 88 ]. Only one reports was grey literature [ 88 ], the remainder were peer-reviewed journals. Six reports (46%) had a primary focus on migrant health [ 56 , 61 , 87 , 88 , 89 , 90 ] while seven reports (54%) also included other at-risk groups in the analysis. Four reports (31%) were also assigned to another SAAP category, two (15%) to area 4 [ 111 , 120 ] and two (15%) to area 8 [ 88 , 115 ].

7. Preventing and reducing the risks posed by non-communicable diseases

Eight reports were categorised to SAAP area 7 (see Fig.  4 ) [ 46 , 51 , 59 , 84 , 85 , 86 , 98 , 119 ] of which six (75%) used qualitative research methods, one (12.5%) used quantitative methods and one (12.5%) used mixed methods. Only one report (12.5%) was grey literature [ 59 ] the remaining seven reports (87.5%) were peer-reviewed journals [ 48 , 87 , 92 , 126 , 127 , 128 , 140 ]. Three reports (37.5%) focused on health behaviours [ 51 , 85 , 98 ], two (25%) on mental health, two (25%) on diabetes and one (12.5%) on chronic disease. Seven reports(87.5%) had a primary focus on migrant health [ 46 , 51 , 59 , 84 , 85 , 86 , 98 ], with the remaining report (12.5%) including ethnic minority groups [ 119 ]. One report (12.5%) was also assigned to SAAP area number 5 [ 119 ].

8. Ensuring ethical and effective health screening and assessment

There were six reports assigned to category 8 (see Fig.  4 ) [ 53 , 88 , 100 , 110 , 115 , 121 ] of which two (33%) used a quantitative research method, three (50%) used a qualitative method and one used mixed methods. One report (14%) was grey literature [ 88 ] the remaining five reports (83%) were peer reviewed journals [ 53 , 100 , 110 , 115 , 121 ]. Three reports (50%) focused on cancer screening in migrant women [ 21 , 100 , 110 ], one (17%) analysed access to HIV testing among African migrants [ 53 ], one (17%) on T.B in healthcare workers [ 72 ] and one (17%) on sexual health [ 36 ]. Three reports (50%) had a primary focus on migrant health [ 53 , 88 , 100 ] while the remaining three reports (50%) included other at-risk groups in the analysis [ 110 , 115 , 121 ]. There were three reports which overlapped with other SAAP areas: one [ 53 ] (17%) was categorised to area 2 while two [ 88 , 115 ] (33%) were categorised to area 6.

9. Improving health information and communication

Three reports were assigned to SAAP area 9 (see Fig.  4 ) [ 31 , 108 , 130 ]. One of these (33%) used a qualitative approach, one (33%) used a quantitative approach and one (33%) used mixed methods. Two [ 108 , 130 ] (66%) were peer-reviewed journal articles and one [ 31 ] (33%) was grey literature. Two reports (66%) focused on improving migrant demographics and health information using databases [ 31 , 108 ] while one (33%) described an information-needs matrix for refugees and asylum seekers [ 130 ]. Two [ 31 , 108 ] included ethnicities in the data while one [ 130 ] had a primary focus on migrant health. Two reports [ 31 , 108 ] (66%) also applied to SAAP area 4 while one report [ 130 ] (33%) was in SAAP area 9 only.

To our knowledge this is the first scoping review conducted on migrant health in Scotland. A previous rapid literature review [ 94 ] found most research focused on health behaviours, mental health, communicable disease and use of and access to healthcare; however, the review limited migrant definition to those who had immigrated within five years and asylum seekers were not included.

In our review, the majority of reports were published from 2013 onwards, aligning with the expansion in migrant research internationally [ 142 ]. 52% used qualitative research methods, 28% used quantitative methods and 20% used mixed methods. 58% focused on migrant health: the remaining papers included other populations or health as part of a wider remit. Research funding was mostly provided by the Scottish Government, NHS, refugee charities and Universities. No studies received funding from the private sector, although this sector has the potential resource and capacity to play a key role in funding future research to improve migrant health in Scotland. Geographically, most studies took place in Glasgow (36%), nationwide (38.5%) or Edinburgh (16%) – other areas were under-represented including Aberdeen (5%), despite being the city with the largest migrant population [ 30 ]. There was a lack of studies in rural localities. These findings concur with a UK migrant health review by Burns et al. [ 23 ] where research was concentrated in larger cities and data was sparse in rural areas relative to the migrant population.

Half of the research identified that was conducted in Glasgow focused on asylum seekers/refugees. Glasgow was previously the only Scottish city to host asylum seekers [ 143 ] and currently supports the most asylum seekers of any local authority in the UK [ 29 ]. In April 2022, the UK government widened the Asylum dispersal scheme to all local authorities [ 144 ]. Around 70% of Scotland’s refugee support services are based in Glasgow and the South-west [ 145 ]. As reduced access to services may impact the health of asylum seekers, research in Glasgow may not be generalizable to other regions of Scotland.

Almost one-third (30%) of all reports focused on asylum seekers and refugees – an overrepresentation given that only 18% of migrants to the UK are asylum seekers [ 146 ] and as low as 2% of all migrants in Scotland [ 147 ]. Asylum seekers and refugees are at risk of poor health due to trauma, difficult journeys, overcrowded camps, poor nutrition and lack of access to healthcare [ 148 ]. They have worse maternity outcomes and increased rates of mental illness [ 149 ]. Increased research on health of asylum seekers and refugees is necessary due to their additional vulnerabilities [ 142 ]. However, asylum seeker’s country of origin was generally not specified. Asylum seekers have heterogenic backgrounds [ 150 ] and nationality and trauma experience affect health status [ 151 ]. Further research focused on specific nationalities of asylum seekers would enhance understanding of the health needs in this population.

Almost one-third (31%) of studies did not specify a migrant group. This concurs with a Norwegian migrant health study by Laue et al. [ 152 ] where 36% of research did not identify country of birth. Where nationality was identified, Polish, African and South Asian were most prevalent. Poles are the largest migrant group in Scotland, however for the other most common immigrant groups of Irish, Italian and Nigerian [ 30 ] there was an absence of research. No studies took place on Nigerian migrants – nine studies indicated African populations, but country of birth was not specified. Since March 2022, 23,000 Ukrainians have migrated to Scotland [ 153 ], however no studies on Ukrainians were identified currently. Research may be underway which is yet to be published.

Only one study explored the impact of Brexit on European migrants’ health despite 56% of migrants to Scotland being EU nationals [ 30 ]. Again, research may be taking place currently, which is yet to be published. No studies involved undocumented migrants despite this populations’ high rates of poor physical/mental health exacerbated by poor housing and working conditions [ 154 ]. An estimated 7.2–9.5% of the workforce in the UK are migrant workers who have higher risks of poor working conditions and injury [ 155 ]. Scotland depends on a migrant workforce for some industries such as agriculture [ 156 ] but only two research papers specified migrant workers.

Most research papers related to the right to health of refugees (SAAP 2), social determinants of health (SAAP 3), public health planning (SAAP 4) and strengthening health systems (SAAP 5). Areas with less research were frameworks for collaborative action (SAAP 1), preventing communicable disease (SAAP 6), preventing non-communicable disease (SAAP 7) and health screening and assessment (SAAP 8). Only three studies related to improving health information and communication (SAAP 9). Lebano et al. [ 12 ] conducted a literature review of migrant health in Europe and found data collection unreliable and disorganised. There is a lack of data on the numbers and types of migrants entering Scotland and research tends not to differentiate between ethnic minorities and migrants [ 94 ]. As poor-quality information hinders surveillance and planning of services SAAP area 9 is an important consideration for increased research.

Villarroel et al. [ 24 ] also found more research in SAAP areas 3 to 5 and less in areas 6 to 9. However, their study returned no results in category 1, collaborative action, or 2, the right to health of refugees, while this study assigned 9% of articles to category 1 and 19% to category 2. Most articles in our study relating to categories 1 and 2 were grey literature, which was excluded from the original Irish scoping review. This highlights a potential difference in the focus of peer-reviewed articles compared to government/refugee charity commissioned reports. Collaborative action and the right to health of refugees and asylum seekers are entwined in Scotland due to the complex policy environment; the social determinants of health such as housing, education, welfare rights and social integration are influenced by a variety of UK and Scottish statutory bodies as well as third sector organisations [ 157 ]. Despite this complexity, organisations work well together [ 158 ]. Further academic research in this area would enhance joint working practices and networks.

A scoping review in the UK [ 23 ] found similar quantities of research corresponding to SAAP areas 3, 2 and 9. However in Scotland areas 1, 5 and 8 were a combined 44% of included papers compared with 27.8% of results on health systems and structures in Burns et al’s [ 23 ] study. Almost half of the articles in SAAP areas 1,5 and 8 were grey literature, which was not included in Burns et al’s [ 23 ] review. Conversely, Burns et al. [ 23 ] found 81.9% of research in the UK related to epidemiology, equivalent to SAAP categories 4,6 and 7. In a Norwegian scoping review of migrant health [ 152 ] 65% of research was related to epidemiological data on health and disease. Only 42% of the research in this current study related to epidemiological data; the quantity of evidence was reduced by excluding combined research from the UK. As Scotland has higher mortality and morbidity than elsewhere in the UK [ 29 ] it is important to undertake further epidemiological research limited to Scotland.

Strengths and weaknesses

Strengths of this review include the use of the WHO’s SAAP categories [ 7 ] to classify data, in accordance with the Villarroel et al’s [ 24 ] study: this means results are linked to policy on migrant health and facilitates comparability to the Irish study results. Additionally results include data on migrant groups, locality, and funding of included papers; these highlight potential omissions for future research consideration. Results include diverse research methods and published and grey literature giving a wide overview of available evidence, reported using the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Scoping Reviews (PRISMA-ScR) checklist (see Additional File 3 ) [ 159 ].

Limitations included the lack of an open-access protocol and search limitations of English language and selected databases. This means some relevant reports may be omitted. Due to time and resource limitations no quality appraisal was planned for included reports. Whilst we did not synthesise the findings for each topic area and migrant group, future systematic reviews could be undertaken to address this limitation and build on this work.

Conclusions

Immigration and ethnic diversity in Scotland have increased since 2002 which is reflected in the expansion of migrant health research. This review highlights evidence gaps including a lack of research in rural areas, undocumented migrants and migrant workers. There is a tendency to cluster asylum seekers together rather than differentiate between national groups. Within the SAAP areas there is less evidence relating to collaborative action, preventing communicable disease, preventing non-communicable disease and health screening and assessment. Further research is required on improving health information and communication for migrant populations in Scotland – a significant omission given the importance of accurate information for health service planning.

Availability of data and materials

All data analysed during this review comes from the papers listed in Additional file 2 .

Abbreviations

European Union

Human Immunodeficiency Virus

National Health Service

Strategy and Action Plan

The Scottish Health and Ethnicity Linkage Study

United Kingdom

World Health Organisation

International Organisation for Migration (IOM). IOM Definition of Migrant. 2024. Available from: https://www.iom.int/about-migration .Cited 2024 Feb 8.

International Organisation for Migration United Nations. World Migration Report. 2022. Available from: available: https://worldmigrationreport.iom.int/wmr-2022-interactive/ .

The United Nations Refugee Angency. Refugee facts: What is a refugee? 2024. Available from: https://www.unrefugees.org/refugee-facts/what-is-a-refugee/ . Cited 2024 Feb 8.

Migration Data Portal. Migration data in Europe. 2023. Available from: https://www.migrationdataportal.org/regional-data-overview/europe#past-and-present-trends . Cited 2023 Aug 22.

International Centre for Migration Policy Development. Migration Outlook 2022 Twelve migration issues to look out for in 2022 Origins, key events and priorities for Europe. 2022. Available from: https://www.icmpd.org/file/download/56783/file/ICMPD%2520Migration%2520Outlook%25202022.pdf .

European Parliament. Exploring migration causes: why people migrate. 2023. Available from: https://www.europarl.europa.eu/news/en/headlines/world/20200624STO81906/exploring-migration-causes-why-people-migrate .

World Health Organisation. Strategic plan: Strategy and Action Plan for Refugee and Migrant Health in the WHO European Region 2016–2022. 2016. Available from: https://www.who.int/publications/i/item/strategic-plan-strategy-and-action-plan-for-refugee-and-migrant-health-in-the-who-european-region-2016-2022 .

Graetz V, Rechel B, Groot W, Norredam M, Pavlova M. Utilization of health care services by migrants in Europe—a systematic literature review. Br Med Bull. 2017;121(1):5–18. Available from: https://www.academic.oup.com/bmb/article-lookup/doi/10.1093/bmb/ldw057 .

Article   CAS   PubMed   Google Scholar  

Hannigan A, O'Donnell P, O'Keeffe M, MacFarlane A. How do Variations in Definitions of “Migrant” and their Application Influence the Access of Migrants to Health Care Services? Copenhagen: WHO Regional Office for Europe; 2016. (Health Evidence Network Synthesis Report, No. 46.) Available from: https://www.ncbi.nlm.nih.gov/books/NBK391032/ .

Rechel B, Mladovsky P, Ingleby D, Mackenbach JP, McKee M. Migration and health in an increasingly diverse Europe. Lancet. 2013;381(9873):1235–45. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0140673612620868 .

Article   PubMed   Google Scholar  

Giannoni M, Franzini L, Masiero G. Migrant integration policies and health inequalities in Europe. BMC Public Health. 2016;16(1):463. Available from:  http://www.bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-016-3095-9 .

Article   PubMed   PubMed Central   Google Scholar  

Lebano A, Hamed S, Bradby H, Gil-Salmerón A, Durá-Ferrandis E, Garcés-Ferrer J, et al. Migrants’ and refugees’ health status and healthcare in Europe: a scoping literature review. BMC Public Health. 2020;20(1):1039. Available from: https://www.bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-020-08749-8 .

Cézard G, Finney N, Kulu H, Marshall A. Ethnic differences in self-assessed health in Scotland: The role of socio-economic status and migrant generation. Popul Space Place. 2022;28(3):e2403. Available from: https://onlinelibrary.wiley.com/doi/10.1002/psp.2403 .

Article   Google Scholar  

Anson J. The migrant mortality advantage: a 70 month follow-up of the brussels population. Eur J Popul. 2004;20(3):191–218.

World Health Organisation. Health of refugees and migrants. WHO European Region. 2018. Available from: https://www.who.int/publications/i/item/health-of-refugees-and-migrants---who-european-region-(2018) .

Mladovsky P. A framework for analysing migrant health policies in Europe. Health Policy (New York). 2009;93(1):55–63. Available from:  https://www.linkinghub.elsevier.com/retrieve/pii/S0168851009001444 .

De Vito E, de Waure C, Specchia ML, Parente P, Azzolini E, Frisicale EM, et al. Are undocumented migrants’ entitlements and barriers to healthcare a public health challenge for the European Union? Public Health Rev. 2016;37(1):13. Available from: http://publichealthreviews.biomedcentral.com/articles/10.1186/s40985-016-0026-3 .

Katikireddi SV, Bhopal R, Quickfall JA. GPs need training and funding in caring for refugees and asylum seekers. BMJ. 2004;328(7442):770.1. Available from:  https://www.bmj.com/lookup/doi/10.1136/bmj.328.7442.770 .

Carballo M, Hargreaves S, Gudumac I, Maclean EC. Evolving migrant crisis in Europe: implications for health systems. Lancet Glob Heal. 2017;5(3):e252-253. Available from:  https://linkinghub.elsevier.com/retrieve/pii/S2214109X17300402 .

Juárez SP, Honkaniemi H, Dunlavy AC, Aldridge RW, Barreto ML, Katikireddi SV et al. Effects of non-health-targeted policies on migrant health: a systematic review and meta-analysis. Lancet Glob Heal. 2019;7(4):e420–35. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2214109X18305606 .

Nielsen SS, Krasnik A. Poorer self-perceived health among migrants and ethnic minorities versus the majority population in Europe: a systematic review. Int J Public Health. 2010;55(5):357–71. Available from: ( http://link.springer.com/10.1007/s00038-010-0145-4 ).

World Health Organsation. World report on the health of refugees and migrants. 2022. Available from: https://www.who.int/publications/i/item/9789240054462 .

Burns R, Zhang CX, Patel P, Eley I, Campos-Matos I, Aldridge RW. Migration health research in the United Kingdom: a scoping review. J Migr Heal. 2021;4:100061. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2666623521000283 .

Villarroel N, Hannigan A, Severoni S, Puthoopparambil S, MacFarlane A. Migrant health research in the Republic of Ireland: a scoping review. BMC Public Health. 2019;19(1):324. Available from: ( https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-6651-2 ).

Scottish Government. Demographic Change in Scotland. 2010. Available from: https://www.gov.scot/binaries/content/documents/govscot/publications/research-and-analysis/2010/11/demographic-change-scotland/documents/0108163-pdf/0108163-pdf/govscot%3Adocument/0108163.pdf .

National Records of Scotland. Projected Population of Scotland (Interim) 2020-based. 2022. Available from: https://www.nrscotland.gov.uk/files/statistics/population-projections/2020-based/pop-proj-2020-scot-nat-pub.pdf .

Scottish Government. Coronavirus (COVID-19) - experiences of vulnerable children, young people, and parents: research. 2021. Available from: https://www.gov.scot/publications/experiences-vulnerable-children-young-people-parents-during-covid-19-pandemic/ .

Scotland’s Census. Scotland’s Census: Ethnicity. 2011. Available from: https://www.scotlandscensus.gov.uk/census-results/at-a-glance/ethnicity/#:~:text=Scotland’spopulationwas96.0%25 .

Walsh D. The changing ethnic profiles of Glasgow and Scotland, and the implications for population health. 2017. Available from: https://www.gcph.co.uk/assets/0000/6255/The_changing_ethnic_profiles_of_Glasgow_and_Scotland.pdf .

National Records of Scotland. Migration Statistics Quarterly Summary for Scotland. 2021. Available from: https://www.nrscotland.gov.uk/files/statistics/migration/quarterly-summary/miration-statistics-quarterly-summary-february-2021.pdf .

The Scottish Ethnicity and Health Research Strategy Working Group. Health in our Multi-ethnic Scotland Future Research Priorities. 2009. Available from: https://www.healthscotland.scot/media/1842/health-in-our-multi-ethnic-scotland-full-report.pdf  .

The Scottish Public Health Observatory. Ethnic minorities: defining ethnicity and race. 2023. Available from: https://www.scotpho.org.uk/population-groups/ethnic-minorities/defining-ethnicity-and-race/ . Cited 2023 Aug 22.

Krasnik A, Bhopal RS, Gruer L, Kumanyika SK. Advancing a unified, global effort to address health disadvantages associated with migration, ethnicity and race. Eur J Public Health. 2018;28(suppl_1). Available from: https://academic.oup.com/eurpub/article/doi/10.1093/eurpub/cky046/4956664 .

Bhopal R, Fischbacher C, Povey C, Chalmers J, Mueller G, Steiner M, et al. Cohort profile: scottish health and ethnicity linkage study of 4.65 million people exploring ethnic variations in disease in Scotland. Int J Epidemiol. 2011;40(5):1168–75. Available from: https://academic.oup.com/ije/article-lookup/doi/10.1093/ije/dyq118 .

Bhopal RS, Gruer L, Cezard G, Douglas A, Steiner MFC, Millard A, et al. Mortality, ethnicity, and country of birth on a national scale, 2001–2013: a retrospective cohort (Scottish Health and Ethnicity Linkage Study). Basu S, editor. Plos Med. 2018;15(3):e1002515. https://doi.org/10.1371/journal.pmed.1002515 . Basu S, editor.

Allik M, Brown D, Dundas R, Leyland AH. Differences in ill health and in socioeconomic inequalities in health by ethnic groups: a cross-sectional study using 2011 Scottish census. Ethn Health. 2022;27(1):190–208. https://doi.org/10.1080/13557858.2019.1643009 ( https://www.tandfonline.com/doi/full/ ).

Watkinson RE, Sutton M, Turner AJ. Ethnic inequalities in health-related quality of life among older adults in England: secondary analysis of a national cross-sectional survey. Lancet Public Hea. 2021;6(3):e145-154.

Fischbacher CM, Cezard G, Bhopal RS, Pearce J, Bansal N. Measures of socioeconomic position are not consistently associated with ethnic differences in cardiovascular disease in Scotland: methods from the Scottish Health and Ethnicity Linkage Study (SHELS). Int J Epidemiol. 2014;43(1):129–39. Available from: https://academic.oup.com/ije/article-lookup/doi/10.1093/ije/dyt237 .

Scottish Government. Characteristics of Recent and Established EEA and non-EEA migrants in Scotland: Analysis of the 2011 Census. 2015. Available from: https://www.gov.scot/publications/characteristics-recent-established-eea-non-eea-migrants-scotland-analysis-2011-census/ .

House of Lords Library. Refugees and asylum-seekers: UK policy. 2022. https://lordslibrary.parliament.uk/refugees-and-asylum-seekers-uk-policy/ .

British Medical Association. Refugee and asylum seeker patient health toolkit. Unique health challenges for refugees and asylum seekers. 2022. Available from: https://www.bma.org.uk/advice-and-support/ethics/refugees-overseas-visitors-and-vulnerable-migrants/refugee-and-asylum-seeker-patient-health-toolkit/unique-health-challenges-for-refugees-and-asylum-seekers .

Khalil H, Peters M, Godfrey CM, McInerney P, Soares CB, Parker D. An evidence-based approach to scoping reviews. Worldviews Evidence-Based Nurs. 2016;13(2):118–23. Available from: https://doi.org/10.1111/wvn.12144 .

Levac D, Colquhoun H, O’Brien KK. Scoping studies: advancing the methodology. Implement Sci. 2010;5(1):69. Available from: ( http://implementationscience.biomedcentral.com/articles/10.1186/1748-5908-5-69 ).

Arksey H, O’Malley L. Scoping studies: towards a methodological framework. Int J Soc Res Methodol. 2005;8(1):19–32.Available from: http://www.tandfonline.com/doi/abs/10.1080/1364557032000119616 ).

Kearns A, Whitley E, Egan M, Tabbner C, Tannahill C. Healthy migrants in an unhealthy city? The Effects of time on the health of migrants living in deprived areas of glasgow. J Int Migr Integr. 2017;18(3):675–98. Available from: http://link.springer.com/10.1007/s12134-016-0497-6 .

PubMed   Google Scholar  

Porqueddu T. Herbal medicines for diabetes control among Indian and Pakistani migrants with diabetes. Anthropol Med. 2017;24(1):17–31. Available from: https://www.tandfonline.com/doi/full/10.1080/13648470.2016.1249338 .

Roshan N. Supporting new communities: a qualitative study of health needs among asylum seekers and refugee communities in North Glasgow final report. 2005. Available from: https://www.stor.scot.nhs.uk/handle/11289/579930 .

Piacentini T, O’Donnell C, Phipps A, Jackson I, Stack N. Moving beyond the ‘language problem’: developing an understanding of the intersections of health, language and immigration status in interpreter-mediated health encounters. Lang Intercult Commun. 2019;19(3):256–71. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1353829214001233 .

Sime D. ‘I think that Polish doctors are better’: Newly arrived migrant children and their parents׳ experiences and views of health services in Scotland. Health Place. 2014;30:86–93. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1353829214001233 .

Steven K, Munoz S, Migrants, Matter. Report of a Peer Researched Project on EU Migrant Health in the Highlands of Scotland. University of the Highlands and Islands. 2016. Available from: https://www.spiritadvocacy.org.uk/assets/Birchwood-Highland-HUG-Migrants-Matter-study-2015-2016.pdf .

Anderson AS, Bush H, Lean M, Bradby H, Williams R, Lea E. Evolution of atherogenic diets in South Asian and Italian women after migration to a higher risk region. J Hum Nutr Diet. 2005;18(1):33–43. Available from: ( https://onlinelibrary.wiley.com/doi/10.1111/j.1365-277X.2004.00584.x ).

Isaacs A, Burns N, Macdonald S, O’Donnell CA. ‘I don’t think there’s anything I can do which can keep me healthy’: how the UK immigration and asylum system shapes the health and wellbeing of refugees and asylum seekers in Scotland. Crit Public Health. 2022;32(3):422–32. Available from: https://www.tandfonline.com/doi/full/10.1080/09581596.2020.1853058 .

Palattiyil G, Sidhva D. Caught in a web of multiple jeopardy: post-traumatic stress disorder and HIV-positive asylum seekers in Scotland. Clin Soc Work J. 2015;43(4):362–74. Available from: http://link.springer.com/10.1007/s10615-015-0542-5 ).

Abdulkadir J, Azzudin A, Buick A, Curtice L, Dzingisai M, Easton D, et al. What do you mean, I have a right to health? Participatory action research on health and human rights. 2016. Available from: https://strathprints.strath.ac.uk/58209/1/Abdulkadir_etal_IPPI_2016_What_do_you_mean_I_have_a_right_to_health.pdf .

Strang A, Quinn N. Integration or isolation? Mapping social connections and well-being amongst refugees in Glasgow. 2014. Available from: https://eresearch.qmu.ac.uk/bitstream/handle/20.500.12289/4139/eResearch%25204139.pdf?sequence=1&isAllowed=y .

Gorman DR, Bielecki K, Larson HJ, Willocks LJ, Craig J, Pollock KG. Comparing vaccination hesitancy in polish migrant parents who accept or refuse nasal flu vaccination for their children. Vaccine. 2020;38(13):2795–9. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0264410X20302255 .

Love J, Vertigans S, Domaszk E, Zdeb K, Love A, Sutton P. Health & ethnicity in Aberdeenshire: a study of Polish in-migrants; a report for the Scottish Health Council. 2007. Available from: https://rgu-repository.worktribe.com/output/247667 .

O’Donnell CA, Higgins M, Chauhan R, Mullen K. Asylum seekers’ expectations of and trust in general practice: a qualitative study. Br J Gen Pract. 2008;58(557):e1-11. Available from: https://bjgp.org/lookup/doi/10.3399/bjgp08X376104 .

Quinn N, Shirjeel S, Siebelt L, Donnelly R, Pietka E. An evaluation of the sanctuary community conversation programme to address mental health stigma with asylum seekers and refugees in Glasgow. 2011. Available from: https://www.healthscotland.com/uploads/documents/5584-SanctuaryCommunityConversationEvaluation.pdf .

Ager A. Community contact and mental health amongst socially isolated refugees in Edinburgh. J Refug Stud. 2002;15(1):71–80. Available from: https://academic.oup.com/jrs/article-lookup/doi/10.1093/jrs/15.1.71 .

Sim JA, Ulanika AA, Katikireddi SV, Gorman D. Out of two bad choices, I took the slightly better one’: Vaccination dilemmas for Scottish and Polish migrant women during the H1N1 influenza pandemic. Public Health. 2011;125(8):505–11. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350611001697 .

Zhao S, Patuano A. International Chinese Students in the UK: association between use of green spaces and lower stress levels. Sustainability. 2021;4(1):89. Available from: https://www.mdpi.com/2071-1050/14/1/89 .

Da Lomba S, Murray N. Women and Children First? Refused asylum seekers’ access to and experiences of maternity care in Glasgow. 2014. Available from: https://strathprints.strath.ac.uk/58655/1/Lomba_Murray_SRC_2014_Women_and_Children_First_Refused_Asylum_Seekers_Access_to_and_Experiences.pdf .

Sørbye IK, Vangen S, Juarez SP, Bolumar F, Morisaki N, Gissler M, et al. Birthweight of babies born to migrant mothers - What role do integration policies play? SSM - Popul Heal. 2019;9:100503. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2352827319301971 .

Teodorowski P, Woods R, Czarnecka M, Kennedy C. Brexit, acculturative stress and mental health among EU citizens in Scotland. Popul Space Place. 2021;27(6). Available from: https://onlinelibrary.wiley.com/doi/10.1002/psp.2436 .

Baillot H, Murray N, Connelly E, Howard N. Tackling Female Genital Mutilation in Scotland: A Scottish model of intervention. 2014. Available from: https://www.celcis.org/application/files/8116/2185/5421/Tackling_Female_Genital_Mutilation_-_A_Scottish_Model_of_Intervention.pdf .

Weishaar HB. Consequences of international migration: a qualitative study on stress among Polish migrant workers in Scotland. Public Health. 2008;122(11):1250–6. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350608000942 .

Weishaar HB. You have to be flexible—coping among polish migrant workers in Scotland. Health Place. 2010;16(5):820–7. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1353829210000432 .

Crowther S, Lau A. Migrant polish women overcoming communication challenges in scottish maternity services: a qualitative descriptive study. Midwifery. 2019;72:30–8. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0266613819300361 .

Fassetta G, Da Lomba S, Quinn N. A healthy start? Experiences of pregnant refugee and asylum seeking women in Scotland. 2016. Available from: https://www.redcross.org.uk/-/media/documents/about-us/research-publications/refugee-support/a-healthy-start-report.pdf .

Positive Action in Housing. 12 months since the Park Inn Tragedy in Glasgow, one in three hotel asylum seekers say their mental health has deteriorated. 2021. Available from: https://www.paih.org/one-in-three-glasgow-asylum-seekers-suffering-depression-and-anxiety .

Strang A. Refugee Peer Education for Health and Well-being. Evaluation Report. 2015. Available from: https://www.scottishrefugeecouncil.org.uk/wp-content/uploads/2019/10/Peer-Education-Evaluation-Report.pdf .

Strang A, Marsden R, Mignard E. The Holistic Integration Service: Learning and Evaluation Year 1. 2014. Available from: https://www.scottishrefugeecouncil.org.uk/wp-content/uploads/2019/10/Holistic-Integration-Service-year-1-evaluation-report.pdf .

British Red Cross. How will we survive? Steps to preventing destitution in the asylum system. 2021. Available from: https://www.redcross.org.uk/-/media/documents/about-us/how-will-we-survive-preventing-destitution-in-the-asylum-system.pdf .

Bhopal RS, Rafnsson SB, Agyemang C, Fagot-Campagna A, Giampaoli S, Hammar N, et al. Mortality from circulatory diseases by specific country of birth across six European countries: test of concept. Eur J Public Health. 2012;22(3):353–9. Available from: https://academic.oup.com/eurpub/article-lookup/doi/10.1093/eurpub/ckr062 .

Rafnsson SB, Bhopal RS, Agyemang C, Fagot-Campagna A, Harding S, Hammar N, et al. Sizable variations in circulatory disease mortality by region and country of birth in six European countries. Eur J Public Health. 2013;23(4):594–605. Available from: https://academic.oup.com/eurpub/article-lookup/doi/10.1093/eurpub/ckt023 ).

de Lima P, Masud Chaudhry M, Whelton R, Arshad R. A study of migrant workers in Grampian. 2007. Available from: . http://www.communitiesscotland.gov.uk/stellent/groups/public/%0Adocuments/webpages/pubcs_019731.pdff .

Ikram UZ, Mackenbach JP, Harding S, Rey G, Bhopal RS, Regidor E, et al. All-cause and cause-specific mortality of different migrant populations in Europe. Eur J Epidemiol. 2016;31(7):655–65. Available from: http://link.springer.com/10.1007/s10654-015-0083-9 .

de Brún T, De-Brún MO, van Weel-Baumgarten E, van Weel C, Dowrick C, Lionis C, et al. Guidelines and training initiatives that support communication in cross-cultural primary-care settings: appraising their implementability using Normalization Process Theory. Fam Pract. 2015;cmv022. Available from: https://academic.oup.com/fampra/article-lookup/doi/10.1093/fampra/cmv022 .

García-Medrano S, Panhofer H. Improving migrant well-being: spontaneous movement as a way to increase the creativity, spontaneity and welfare of migrants in Glasgow. Body Mov Danc Psychother. 2020;15(3):189–203. Available from: https://www.tandfonline.com/doi/full/10.1080/17432979.2020.1767208 .

Jamil NA, Gray SR, Fraser WD, Fielding S, Macdonald HM. The relationship between vitamin D status and muscle strength in young healthy adults from sunny climate countries currently living in the northeast of Scotland. Osteoporos Int. 2017;28(4):1433–43. Available from: http://link.springer.com/10.1007/s00198-016-3901-3 .

Kaneoka M, Spence W. The cultural context of sexual and reproductive health support: an exploration of sexual and reproductive health literacy among female Asylum Seekers and Refugees in Glasgow. Int J Migr Heal Soc Care. 2019;16(1):46–64. Available from: https://www.emerald.com/insight/content/doi/10.1108/IJMHSC-01-2019-0002/full/html .

O’Donnell CA, Higgins M, Chauhan R, Mullen K. They think we’re OK and we know we’re not. A qualitative study of asylum seekers’ access, knowledge and views to health care in the UK. BMC Health Serv Res. 2007;7(1):75. Available from: https://bmchealthservres.biomedcentral.com/articles/10.1186/1472-6963-7-75 .

Cooper M, Harding S, Mullen K, O’Donnell C. ‘A chronic disease is a disease which keeps coming back … it is like the flu’: chronic disease risk perception and explanatory models among French- and Swahili-speaking African migrants. Ethn Health. 2012;17(6):597–613. Available from: http://www.tandfonline.com/doi/abs/10.1080/13557858.2012.740003 .

Ezika EA. An exploration of smoking behavior of african male immigrants living in glasgow. Tob Use Insights. 2014;7:TUI .S13262. Available from: http://journals.sagepub.com/doi/10.4137/TUI.S13262 .

Karadzhov D, White R. Between the whispers of the devil and the revelation of the word : christian clergy’s mental health literacy and pastoral support for BME congregants. J Spiritual Ment Heal. 2020;22(2):147–72. Available from: https://www.tandfonline.com/doi/full/10.1080/19349637.2018.1537755 ).

Yakubu BD, Simkhada P, van Teijlingen E, Eboh W. Sexual health information and uptake of sexual health services by African women in Scotland: a pilot study. Int J Heal Promot Educ. 2010;48(3):79–84. Available from: http://www.tandfonline.com/doi/abs/10.1080/14635240.2010.10708186 .

Goff J, Kay K, Lima M, Shallangwa S, We All Have A. Different Consciousness About It: Exploring the Sexual Health Needs of People From African Communities in Scotland. 2021. Available from: https://www.waverleycare.org/wp-content/uploads/2023/05/We_All_Have_Different_Consciousness_About_It_Report.pdf .

Bielecki K, Craig J, Willocks LJ, Pollock KG, Gorman DR. Impact of an influenza information pamphlet on vaccination uptake among Polish pupils in Edinburgh, Scotland and the role of social media in parental decision making. BMC Public Health. 2020;20(1):1381. Available from: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-020-09481-z .

Article   CAS   PubMed   PubMed Central   Google Scholar  

Gorman DR, Bielecki K, Willocks LJ, Pollock KG. A qualitative study of vaccination behaviour amongst female Polish migrants in Edinburgh, Scotland. Vaccine. 2019;37(20):2741–7. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0264410X19304220 .

Bak-Klimek A, Karatzias T, Elliott L, MacLean R. The determinants of well-being among polish economic immigrants. Testing the sustainable happiness model in migrant population. J Happiness Stud. 2018;19(6):1565–88. Available from: http://link.springer.com/10.1007/s10902-017-9877-7 .

Cheung NF. The cultural and social meanings of childbearing for Chinese and Scottish women in Scotland. Midwifery. 2002;18(4):279–95. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0266613802903281 .

Papadaki A, Scott J. The impact on eating habits of temporary translocation from a Mediterranean to a Northern European environment. Eur J Clin Nutr. 2002;56(5):455–61. Available from: https://www.nature.com/articles/1601337 .

McCann A, Mackie P. Improving the Health of Migrants to Scotland: An update for Scottish Directors of Public Health. 2016. Available from: https://www.scotphn.net/wp-content/uploads/2016/04/2016_03_23-Migrant-Health-Report-FINAL-1.pdf .

Ahmed A, Cameron S, Dickson C, Mountain K. Arabic-speaking students’ primary care experiences in Scotland. Community Pract J Community Pract Heal Visit Assoc. 2010;83(2):23–6.

Google Scholar  

Bray J, Gorman D, Dundas K, Sim J. Obstetric care of New European migrants in Scotland: an audit of antenatal care, obstetric outcomes and communication. Scott Med J. 2010;55(3):26–31. Available from: ( http://journals.sagepub.com/doi/10.1258/rsmsmj.55.3.26 .

Cheung NF. Choice and control as experienced by Chinese and Scottish childbearing women in Scotland. Midwifery. 2002;18(3):200–13. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0266613802903153 .

Spence W, Zhu L. Perceptions of smoking cessation among Glasgow’s Chinese community. Tob Prev Cessat. 2017;3(October). Available from: http://www.journalssystem.com/tpc/Perceptions-of-smoking-cessation-among-Glasgow-s-Chinese-community,77942,0,2.html .

Gorman DR, Katikireddi SV, Morris C, Chalmers JWT, Sim J, Szamotulska K, et al. Ethnic variation in maternity care: a comparison of Polish and Scottish women delivering in Scotland 2004–2009. Public Health. 2014;128(3):262–7. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350613003910 .

Gorman DR, Porteous LA. Influences on Polish migrants’ breast screening uptake in Lothian, Scotland. Public Health. 2018;158:86–92. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350617304018 .

Hogg R, de Kok B, Netto G, Hanley J, Haycock-Stuart E. Supporting Pakistani and Chinese families with young children: perspectives of mothers and health visitors. Child Care Health Dev. 2015;41(3):416–23. Available from: https://onlinelibrary.wiley.com/doi/10.1111/cch.12154 .

Kearns A, Whitley E. Health, Wellbeing and Social Inclusion of Migrants in North Glasgow. 2010. Available from: https://www.gowellonline.com/assets/0000/0521/Health_Wellbeing_and_Social_Inclusion_of_Migrants_in_North_Glasgow.pdf .

Poole L, Adamson K. Report on the Situation of the Roma Community in Govanhill, Glasgow. 2008. Available from: https://www.bemis.org.uk/resources/gt/scotland/reportonthesituationoftheromacommunityingovanhill,Glasgow.pdf .

Schofield L, Walsh D, Feng Z, Buchanan D, Dibben C, Fischbacher C, et al. Does ethnic diversity explain intra-UK variation in mortality? A longitudinal cohort study. BMJ Open. 2019;9(3):e024563. Available from: https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2018-024563 .

Unger HW, McCallum AD, Ukachukwu V, McGoldrick C, Perrow K, Latin G, et al. Imported malaria in Scotland – an overview of surveillance, reporting and trends. Travel Med Infect Dis. 2011;9(6):289–97. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1477893911001074 .

Young I, Flowers P, McDaid LM. Barriers to uptake and use of pre-exposure prophylaxis (PrEP) among communities most affected by HIV in the UK: findings from a qualitative study in Scotland. BMJ Open. 2014;4(11):e005717. Available from: https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2014-005717 .

Young I, Flowers P, McDaid LM. Key factors in the acceptability of treatment as prevention (TasP) in Scotland: a qualitative study with communities affected by HIV. Sex Transm Infect. 2015;91(4):269–74. Available from: https://sti.bmj.com/lookup/doi/10.1136/sextrans-2014-051711 .

Bhopal R, Cm FI, Teiner SM, Halmers CJ, Ovey PC, Amieson J. Ethnicity and health in Scotland: Can we fill the information gap ? A demonstration project focusing on coronary heart disease and linkage of census and health records. Ethics. 2005. Available from: http://www.cphs.mvm.ed.ac.uk/docs/Retrocodingfinalreport.pdf .

Cezard GI, Bhopal RS, Ward HJT, Bansal N, Bhala N. Ethnic variations in upper gastrointestinal hospitalizations and deaths: the Scottish Health and Ethnicity Linkage Study. Eur J Public Health. 2016;26(2):254–60. Available from: https://academic.oup.com/eurpub/article-lookup/doi/10.1093/eurpub/ckv182 .

Christie-de Jong F, Kotzur M, Amiri R, Ling J, Mooney JD, Robb KA. Qualitative evaluation of a codesigned faith-based intervention for muslim women in Scotland to encourage uptake of breast, colorectal and cervical cancer screening. BMJ Open. 2022;12(5):e058739. Available from: https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2021-058739 .

Cree VE, Sidhva D. Children and HIV in Scotland: findings from a cross-sector needs assessment of children and young people infected and affected by HIV in Scotland. Br J Soc Work. 2011;41(8):1586–603. Available from: https://academic.oup.com/bjsw/article-lookup/doi/10.1093/bjsw/bcr036 .

Gallimore A, Irshad T, Cooper M, Cameron S. Influence of culture, religion and experience on the decision of Pakistani women in Lothian, Scotland to use postnatal contraception: a qualitative study. BMJ Sex Reprod Heal. 2021;47(1):43–8. Available from: https://jfprhc.bmj.com/lookup/doi/10.1136/bmjsrh-2019-200497 .

Gruer LD, Cézard GI, Wallace LA, Hutchinson SJ, Douglas AF, Buchanan D, et al. Complex differences in infection rates between ethnic groups in Scotland: a retrospective, national census-linked cohort study of 1.65 million cases. J Public Health (Bangkok). 2022;44(1):60–9. Available from: https://academic.oup.com/jpubhealth/article/44/1/60/6106111 .

Article   CAS   Google Scholar  

Bhala N, Cézard G, Ward HJT, Bansal N, Bhopal R. Ethnic variations in liver- and alcohol-related disease hospitalisations and mortality: the Scottish health and ethnicity linkage study. Alcohol Alcohol. 2016;51(5):593–601. Available from: https://academic.oup.com/alcalc/article-lookup/doi/10.1093/alcalc/agw018 .

Pollock KG, McDonald E, Smith-Palmer A, Johnston F, Ahmed S. Tuberculosis in healthcare workers, Scotland. Scott Med J. 2017;62(3):101–3. Available from: http://journals.sagepub.com/doi/10.1177/0036933017727963 .

Gruer LD, Millard AD, Williams LJ, Bhopal RS, Katikireddi SV, Cézard GI, et al. Differences in all-cause hospitalisation by ethnic group: a data linkage cohort study of 4.62 million people in Scotland, 2001–2013. Public Health. 2018;161:5–11. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350618301501 .

Jackson C, Bedford H, Cheater FM, Condon L, Emslie C, Ireland L, et al. Needles, Jabs and Jags: a qualitative exploration of barriers and facilitators to child and adult immunisation uptake among Gypsies, Travellers and Roma. BMC Public Health. 2017;17(1):254. Available from: http://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-017-4178-y .

John JR, Curry G, Cunningham-Burley S. Exploring ethnic minority women’s experiences of maternity care during the SARS-CoV-2 pandemic: a qualitative study. BMJ Open. 2021;11(9):e050666. Available from: https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2021-050666 .

Lawton J, Ahmad N, Hanna L, Douglas M, Hallowell N. Diabetes service provision: a qualitative study of the experiences and views of Pakistani and Indian patients with Type 2 diabetes. Diabet Med. 2006;23(9):1003–7. Available from: https://onlinelibrary.wiley.com/doi/10.1111/j.1464-5491.2006.01922.x .

Livingston MR, Shaw LE, Codere G, Goldberg DJ. Human immunodeficiency virus acquired heterosexually abroad: expert panel assessment of the indigenous/nonindigenous to the united kingdom status of cases. J Travel Med. 2006;12(1):19–25. Available from: https://academic.oup.com/jtm/article-lookup/doi/10.2310/7060.2005.00005 .

Nelson M, Patton A, Robb K, Weller D, Sheikh A, Ragupathy K, et al. Experiences of cervical screening participation and non-participation in women from minority ethnic populations in Scotland. Heal Expect. 2021;24(4):1459–72. Available from: https://onlinelibrary.wiley.com/doi/10.1111/hex.13287 .

Noble G, Okpo E, Tonna I, Fielding S. Factors associated with late HIV diagnosis in North-East Scotland: a six-year retrospective study. Public Health. 2016;139:36–43. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0033350616301020 .

Gillespie M. Trapped: Destitution and Asylum in Scotland. 2012. Available from: http://www.rst.org.uk/wp-content/uploads/2012/11/Trapped-destitution-and-asylum-summary-final-compressed-pictures.pdf .

Hopkins P, Hill M. The needs and strengths of unaccompanied asylum-seeking children and young people in Scotland. Child Fam Soc Work. 2010;15(4):399–408. Available from: https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2206.2010.00687.x .

Marsden R, Harris C. “We started life again”: Integration experiences of refugee families reuniting in Glasgow. 2015. Available from: https://www.refworld.org/docid/560cde294.html .

Martzoukou K, Burnett S. Exploring the everyday life information needs and the socio-cultural adaptation barriers of Syrian refugees in Scotland. J Doc. 2018;74(5):1104–32. Available from: https://www.emerald.com/insight/content/doi/10.1108/JD-10-2017-0142/full/html .

McKenna R. From pillar to post: Destitution among people refused asylum in Scotland. 2019; Available from: https://www.rst.org.uk/wp-content/uploads/2019/03/From-Pillar-to-Post-Feb-2019.pdf .

Independent Commission of Inquiry. Failings in the provision of care to New Scots during the Covid pandemic: Part 2. 2022. Available from: https://static1.squarespace.com/static/62af1289a666c80e00b17253/t/636b9190408f81778746eaa7/1667994032702/AIS+Phase+2+Report+Full.pdf .

Trevena P, Gawlewicz A, Wright S. Addressing the needs of Scotland’s migrant and minority ethnic populations under Covid-19: lessons for the future. 2022. Available from: https://migrantessentialworkers.com/wp-content/uploads/2022/11/SC-Migrant-C19-Innovations.pdf .

Oduntan O, Ruthven I. The information needs matrix: a navigational guide for refugee integration. Inf Process Manag. 2019;56(3):791–808. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0306457318306939 .

Sime D, Fox R, Migrant C. Social capital and access to services post-migration: transitions, negotiations and complex agencies. Child Soc. 2015;29(6):524–34. Available from: https://onlinelibrary.wiley.com/doi/10.1111/chso.12092 .

Strang A, Baillot H, Mignard E. Insights into integration pathways. New Scots and the Holistic Integration Service. A report drawing on year two of the Holistic Integration Service. 2015. Available from: https://scottishrefugeecouncil.org.uk/wp-content/uploads/2019/10/Holistic-Integration-Service-Year-2-report.pdf .

Weir KEA, Wilson SJ, Gorman DR. The Syrian vulnerable person resettlement programme: evaluation of Edinburgh’s reception arrangements. J Public Health (Bangkok). 2018;40(3):451–60. Available from: https://academic.oup.com/jpubhealth/article/40/3/451/4600209 .

Hammond CN. Scots 2- Engagement analysis of the New Scot Refugee Integration Strategy 2018–2022. 2018. Available from: https://www.gov.scot/binaries/content/documents/govscot/publications/research-and-analysis/2018/06/news-scots-2-engagement-analysis-new-scots-refugee-integration-strategy/documents/00537019-pdf/00537019-pdf/govscot%3Adocument/00537019.pdf .

Blake Stevenson. A8 Nationals in Glasgow. 2007. Available from: http://crosshillandgovanhill.org.uk/grindocs/A8NationalsinGlasgow.pdf .

Ajetunmobi O, Whyte B, Chalmers J, Fleming M, Stockton D, Wood R. Informing the ‘early years’ agenda in Scotland: understanding infant feeding patterns using linked datasets. J Epidemiol Community Health. 2014;68(1):83–92. Available from: https://jech.bmj.com/lookup/doi/10.1136/jech-2013-202718 .

Laidlaw K, Wang D, Coelho C, Power M. Attitudes to ageing and expectations for filial piety across Chinese and British cultures: a pilot exploratory evaluation. Aging Ment Health. 2010;14(3):283–92. Available from: http://www.tandfonline.com/doi/abs/10.1080/13607860903483060 .

Marsden R, Aldegheri E, Khan A, Lowe M, Strang A, Salinas E, et al. “What’s going on?” A study into destitution and poverty faced by asylum seekers and refugees in Scotland. 2005. Available from: http://www.rst.org.uk/wp-content/uploads/2012/11/Whats_going_on_A_study.pdf .

Quinn N. Participatory action research with asylum seekers and refugees experiencing stigma and discrimination: the experience from Scotland. Disabil Soc. 2014;29(1):58–70. Available from: http://www.tandfonline.com/doi/abs/10.1080/09687599.2013.769863 .

British Red Cross, Refugee Survival Trust. How will we survive? Steps to preventing destitution in the asylum system. 2021. Available from: https://mcusercontent.com/c17c136fc126588cb51e5471d/files/a35dd0e1-d785-f962-6a41-01e928493775/DASS_Research_Report_2021.pdf .

O’Donnell R, Angus K, McCulloch P, Amos A, Greaves L, Semple S. Fathers’ views and experiences of creating a smoke-free home: a scoping review. Int J Environ Res Public Health. 2019;16(24):5164. Available from: https://www.mdpi.com/1660-4601/16/24/5164 .

Sweileh WM, Wickramage K, Pottie K, Hui C, Roberts B, Sawalha AF, et al. Bibliometric analysis of global migration health research in peer-reviewed literature (2000–2016). BMC Public Health. 2018;18(1):777. Available from: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-018-5689-x .

Wren K. Supporting asylum seekers and refugees in glasgow: the role of multi-agency networks. J Refug Stud. 2007;20(3):391–413. Available from: https://academic.oup.com/jrs/article-lookup/doi/10.1093/jrs/fem006 .

UK Government Home Office. A Fairer Asylum Accommodation System. 2022. Available from: https://www.emcouncils.gov.uk/write/Migration/Asylum_Dispersal_Factsheet_PDF.pdf .

Scottish Refugee Council. Scotland’s Welcome: an analysis of community support for refugee integration. 2020. Available from https://scottishrefugeecouncil.org.uk/wp-content/uploads/2021/01/Community-support-analysis-2020.pdf .

Sturge G, UK Parliament House of Commons Library Asylum statistics Research Briefing. 2023. Available from: https://commonslibrary.parliament.uk/research-briefings/sn01403/#:~:text=IntheyearendingJune,ofimmigrantstotheUK .

The Migration Observatory. Where do migrants live in the UK? The Migration Observatory at the University of Oxford. 2022. Available from: https://migrationobservatory.ox.ac.uk/resources/briefings/where-do-migrants-live-in-the-uk .

Pavli A, Maltezou H. Health problems of newly arrived migrants and refugees in Europe. J Travel Med. 2017;24(4). Available from: http://academic.oup.com/jtm/article/doi/10.1093/jtm/tax016/3095987/Health-problems-of-newly-arrived-migrants-and .

Humphris R, Bradby H. Health Status of Refugees and Asylum Seekers in Europe. In: Oxford Research Encyclopedia of Global Public Health. Oxford University Press; 2017. Available from: https://oxfordre.com/publichealth/view/10.1093/acrefore/9780190632366.001.0001/acrefore-9780190632366-e-8 .

Bradby H, Humphris R, Newall D, Phillimore J. Public Health Aspects of Migrant Health: A Review of the Evidence on Health Status for Refugees and Asylum Seekers in the European Region. (Health Evidence Network Synthesis Report, No. 44.) ANNEX 2, DEFINITIONS OF REFUGEES, ASYLUM SEEKERS AND MIGRANTS IN THE LITERATURE. Copenhagen: Eerat; 2015. Available from:  https://www.ncbi.nlm.nih.gov/books/NBK379415/ .

Gerritsen AAM, Bramsen I, Devillé W, van Willigen LHM, Hovens JE, van der Ploeg HM. Physical and mental health of Afghan, Iranian and Somali asylum seekers and refugees living in the Netherlands. Soc Psychiatry Psychiatr Epidemiol. 2006;41(1):18–26. Available from: http://link.springer.com/10.1007/s00127-005-0003-5 .

Laue J, Diaz E, Eriksen L, Risør T. Migration health research in Norway: a scoping review. Scand J Public Health. 2023;51(3):381–90. Available from: http://journals.sagepub.com/doi/10.1177/14034948211032494 .

Scottish Refugee Council. Ukraine response one year on. 2023. Available from: https://scottishrefugeecouncil.org.uk/ukraine-response-one-year-on/ . Cited 2023 Aug 26.

Woodward A, Howard N, Wolffers I. Health and access to care for undocumented migrants living in the European Union: a scoping review. Health Policy Plan. 2014;29(7):818–30. Available from: https://academic.oup.com/heapol/article-lookup/doi/10.1093/heapol/czt061 .

Simon J, Kiss N, Laszewska A, Mayer S. Public health aspects of migrant health: a review of the evidence on health status for labour migrants in the European Region. Health Evidence Network Synthesis Report 43. 2015. Available from: http://www.epgencms.europarl.europa.eu/cmsdata/upload/114f16b6-1667-44ab-802b-a5a83dd50af0/WHO-HEN-Report-A5-1-Labour-FINAL_EN.pdf .

Scottish Government. Seasonal migrant workers in Scottish agriculture: research report. 2023. Available from: https://www.gov.scot/publications/seasonal-migrant-workers-scottish-agriculture/pages/10/ .

Scottish Government. New Scots: refugee integration strategy 2018–2022. 2018. Available from: https://www.gov.scot/publications/new-scots-refugee-integration-strategy-2018-2022/pages/11/ .

Oliva A, Palavra V, Caloun J. Refugees in Scotland: understanding the policy domain. 2016. Available from: https://www.academia.edu/34097718/REFUGEES_IN_SCOTLAND_UNDERSTANDING_THE_POLICY_DOMAIN .

Tricco AC, Lillie E, Zarin W, O’Brien KK, Colquhoun H, Levac D, et al. PRISMA extension for scoping reviews (PRISMA-ScR): checklist and explanation. Ann Intern Med. 2018;169(7):467–73. Available from: https://www.acpjournals.org/doi/10.7326/M18-0850 .

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Acknowledgements

Thank-you to Professor Anne MacFarlane and PHD student Anne Cronin, of the University of Limerick, Ireland for sharing the coding guidelines currently used in an update to Villarroel et. al’s 2019 study on Migrant Health in the Republic of Ireland.

No funding was received for this work, which was undertaken as G. Petrie’s Master of Public Health dissertation module at the University of Stirling.

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Petrie, G., Angus, K. & O’Donnell, R. A scoping review of academic and grey literature on migrant health research conducted in Scotland. BMC Public Health 24 , 1156 (2024). https://doi.org/10.1186/s12889-024-18628-1

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Parvulescu wins $1.2M European Union grant

Project will investigate origins of comparative literature

Anca Parvulescu , the Liselotte Dieckmann Professor in Comparative Literature and a professor of English, both in Arts & Sciences, at Washington University in St. Louis, will serve as principal investigator for a $1.2 million grant exploring the history of comparatism and the origins of the comparative method.

The project is funded by the European Union, through a 2 1/2-year Next Generation grant, and is hosted by Babeș-Bolyai University in Cluj, Romania. Parvulescu’s team of 17 international scholars ranges from tenured faculty to doctoral candidates and postdoctoral fellows.

“We’re interested in how the comparative method develops on the margins of European empires,” said Parvulescu, author, with sociologist Manuela Boatcă, of “Creolizing the Modern: Transylvania Across Empires” (2022), which won awards from both the American Comparative Literature Association and the American Sociological Association. “Comparative literature is theoretically about multilingualism, but this ideal often gets filtered through imperial policy. We end up with a hierarchy that assumes the superiority of Western European literary traditions.”

While the ability to make comparisons is a fundamental aspect of human cognition, the comparative method represents a specific intellectual tradition, one that arose from 19th-century linguistics to shape a variety of disciplines across the humanities, sciences and social sciences.

Formerly part of the Austro-Hungarian Empire, Cluj (Kolozsvár in Hungarian and Klausenburg in German) is arguably the birthplace of comparative literature, thanks to the 1877 launch of Acta Comparationis Litterarum Universarum, a polyglot journal edited by Sámuel Brassai and Hugó Meltzl.

“It was a utopian moment,” Parvulescu said. “The assumption was that if you were writing on Cervantes, you’d publish in Spanish. If you were writing on Goethe, you’d publish in German. But this didn’t always happen; multilingualism ended up being implemented in selective ways. The analysis of a Romani-language poem was framed in German.”

In the metropolitan hearts of European colonial powers, cultural comparison could take triumphalist turns. But on the fringes, the interplay of local languages reflected political jostling. In Cluj, for example, German and Hungarian maintained an uneasy accord with the French world of letters, but were in marked tension with regional languages, such as Romanian, Yiddish, Romani and Armenian.

“We’re looking at this cultural moment as a case study,” Parvulescu said. “But we’re also positing it as a global moment in which something similar is happening in other parts of the world. We’re interested in how so-called minor literary traditions thought about their relation to the big centers but also to each other. What emerges from this study is an expansive, heterogenous archive of comparative figures and approaches — at a global scale. In turn, methodological tools derived from this history enrich our sense of what comparatism can be today.”

Parvulescu recounts the story of a 1926 visit to Romania by Rabindranath Tagore, the Nobel Prize-winning Bengali writer, poet and composer. “He was welcomed as a hero,” Parvulescu said. “Romanian intellectuals were really invested in a non-European figure with whom they could bridge cultural relations horizontally, as opposed to the hierarchies of Paris or Berlin.”

Today, these hierarchies may have shifted, with English emerging as the dominant language of globalization, but the tensions remain familiar.

“We often refer to it as the monolingual paradigm,” Parvulescu said, “It’s a convergence toward one language that assumes a particular place in the politics of knowledge. Knowledge produced in that language is seen as superior to knowledge produced in other languages — if the latter are on the table at all. Today, this language is English. Our project reframes the politics of global English (and its attendant sociology of translation) against a long and complex history of monolingualization.”

In addition to WashU and Babeș-Bolyai, members of Parvulecu’s team are affiliated with the University of Freiburg, the University of North Carolina and the University of California, Los Angeles. Parvulescu noted that similar comparatist projects are underway at the University of Cambridge, the University of Bielefeld and the University of Warwick. She hopes to build on the work of the grant through WashU’s Center for the Humanities in Arts & Sciences.

Stephanie Kirk, director of the Center for the Humanities, said the grant “opens up exciting possibilities. I look forward to seeing how we might create programming, publication and U.S.-based grant writing opportunities, as well as collaboration among WashU humanities faculty and graduate students from different fields and language traditions.”

Parvulescu concluded: “I think the task of comparative literature is to do the work of respecting and cultivating languages around the world. Comparative literature insists, against all odds, on multilingualism as a value.”

Comments and respectful dialogue are encouraged, but content will be moderated. Please, no personal attacks, obscenity or profanity, selling of commercial products, or endorsements of political candidates or positions. We reserve the right to remove any inappropriate comments. We also cannot address individual medical concerns or provide medical advice in this forum.

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The American Trends Panel survey methodology

The American Trends Panel (ATP), created by Pew Research Center, is a nationally representative panel of randomly selected U.S. adults. Panelists participate via self-administered web surveys. Panelists who do not have internet access at home are provided with a tablet and wireless internet connection. Interviews are conducted in both English and Spanish. The panel is being managed by Ipsos.

Data in this report is drawn from ATP Wave 142, conducted from Feb. 7 to 11, 2024, and includes an oversample of non-Hispanic Asian adults, non-Hispanic Black men, and Hispanic men in order to provide more precise estimates of the opinions and experiences of these smaller demographic subgroups. These oversampled groups are weighted back to reflect their correct proportions in the population. A total of 10,133 panelists responded out of 11,117 who were sampled, for a response rate of 91%. The cumulative response rate accounting for nonresponse to the recruitment surveys and attrition is 3%. The break-off rate among panelists who logged on to the survey and completed at least one item is less than 1%. The margin of sampling error for the full sample of 10,133 respondents is plus or minus 1.5 percentage points.

Panel recruitment

The ATP was created in 2014, with the first cohort of panelists invited to join the panel at the end of a large, national, landline and cellphone random-digit-dial survey that was conducted in both English and Spanish. Two additional recruitments were conducted using the same method in 2015 and 2017, respectively. Across these three surveys, a total of 19,718 adults were invited to join the ATP, of whom 9,942 (50%) agreed to participate.

In August 2018, the ATP switched from telephone to address-based sampling (ABS) recruitment. A study cover letter and a pre-incentive are mailed to a stratified, random sample of households selected from the U.S. Postal Service’s Delivery Sequence File. This Postal Service file has been estimated to cover as much as 98% of the population, although some studies suggest that the coverage could be in the low 90% range. 1 Within each sampled household, the adult with the next birthday is asked to participate. Other details of the ABS recruitment protocol have changed over time but are available upon request. 2

We have recruited a national sample of U.S. adults to the ATP approximately once per year since 2014. In some years, the recruitment has included additional efforts (known as an “oversample”) to boost sample size with underrepresented groups. For example, Hispanic adults, Black adults and Asian adults were oversampled in 2019, 2022 and 2023, respectively.

Across the six address-based recruitments, a total of 23,862 adults were invited to join the ATP, of whom 20,917 agreed to join the panel and completed an initial profile survey. Of the 30,859 individuals who have ever joined the ATP, 11,920 remained active panelists and continued to receive survey invitations at the time this survey was conducted.

The American Trends Panel never uses breakout routers or chains that direct respondents to additional surveys.

Sample design

The overall target population for this survey was noninstitutionalized persons ages 18 and older living in the U.S., including Alaska and Hawaii. It featured a stratified random sample from the ATP in which Hispanic men, non-Hispanic Black men and non-Hispanic Asian adults were selected with certainty. The remaining panelists were sampled at rates designed to ensure that the share of respondents in each stratum is proportional to its share of the U.S. adult population to the greatest extent possible. Respondent weights are adjusted to account for differential probabilities of selection as described in the Weighting section below.

Questionnaire development and testing

The questionnaire was developed by Pew Research Center in consultation with Ipsos. The web program was rigorously tested on both PC and mobile devices by the Ipsos project management team and Pew Research Center researchers. The Ipsos project management team also populated test data that was analyzed in SPSS to ensure the logic and randomizations were working as intended before launching the survey.

All respondents were offered a post-paid incentive for their participation. Respondents could choose to receive the post-paid incentive in the form of a check or a gift code to Amazon.com or could choose to decline the incentive. Incentive amounts ranged from $5 to $15 depending on whether the respondent belongs to a part of the population that is harder or easier to reach. Differential incentive amounts were designed to increase panel survey participation among groups that traditionally have low survey response propensities.

Data collection protocol

The data collection field period for this survey was Feb. 7 to 11, 2024. Postcard notifications were mailed to a subset of ATP panelists with a known residential address on Feb. 7. 3

Invitations were sent out in two separate launches: soft launch and full launch. Sixty panelists were included in the soft launch, which began with an initial invitation sent on the morning of Feb. 7. The ATP panelists chosen for the initial soft launch were known responders who had completed previous ATP surveys within one day of receiving their invitation. All remaining English- and Spanish-speaking sampled panelists were included in the full launch and were sent an invitation on the afternoon of Feb. 7.

All panelists with an email address received an email invitation and up to two email reminders if they did not respond to the survey. All ATP panelists who consented to SMS messages received an SMS invitation and up to two SMS reminders.

Data quality checks

To ensure high-quality data, the Center’s researchers performed data quality checks to identify any respondents showing clear patterns of satisficing. This includes checking for whether respondents left questions blank at very high rates or always selected the first or last answer presented. As a result of this checking, two ATP respondents were removed from the survey dataset prior to weighting and analysis.

The ATP data is weighted in a multistep process that accounts for multiple stages of sampling and nonresponse that occur at different points in the survey process. First, each panelist begins with a base weight that reflects their probability of selection for their initial recruitment survey. These weights are then rescaled and adjusted to account for changes in the design of ATP recruitment surveys from year to year. Finally, the weights are calibrated to align with the population benchmarks in the accompanying table to correct for nonresponse to recruitment surveys and panel attrition. If only a subsample of panelists was invited to participate in the wave, this weight is adjusted to account for any differential probabilities of selection.

Among the panelists who completed the survey, this weight is then calibrated again to align with the population benchmarks identified in the accompanying table and trimmed at the 2nd and 98th percentiles to reduce the loss in precision stemming from variance in the weights. This trimming is performed separately among non-Hispanic Black, non-Hispanic Asian, Hispanic and all other respondents. Sampling errors and tests of statistical significance take into account the effect of weighting.

The following table shows the unweighted sample sizes and the error attributable to sampling that would be expected at the 95% level of confidence for different groups in the survey.

Sample sizes and sampling errors for other subgroups are available upon request. In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of opinion polls.

Dispositions and response rates

© Pew Research Center 2024

• AAPOR Task Force on Address-based Sampling. 2016. “AAPOR Report: Address-based Sampling.” ↩
• Email [email protected] . ↩
• Postcard notifications are sent to 1) panelists who have been provided with a tablet to take ATP surveys, 2) panelists who were recruited within the last two years, and 3) panelists recruited prior to the last two years who opt to continue receiving postcard notifications. ↩

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Analytical Methods

New insight from maldi-tof ms and multivariate data analysis on the botanical origin of polysaccharide-based paint binders in ancient egypt †.

* Corresponding authors

a Art Institute of Chicago, Department of Conservation and Science, 111 S. Michigan Ave, Chicago, IL 60603, USA E-mail: [email protected]

b Center for Scientific Studies in the Arts, Northwestern University, Tech Building, 2145 Sheridan Road, Evanston, IL 60208, USA

c Radboud University, Institute for Molecules and Materials, (Analytical Chemistry & Chemometrics), P. O. Box 9010, Nijmegen, 6500 GL, The Netherlands

Polysaccharide-based materials of plant origin are known to have been used as binding media in paint and ground layers of artifacts from ancient Egypt, including wall paintings, cartonnages and sarcophagi. The use of gums from Acacia , Astragalus and Prunus genera has been suggested in the literature on the basis of their qualitative or quantitative monosaccharide profile after complete chemical hydrolysis. The introduction of partial enzymatic digestion of the polysaccharide material, followed by analysis of the released oligosaccharides by matrix assisted laser desorption ionization-time-of-flight mass spectrometry, has proved effective in discriminating among gums from different genera, as well as among species within the Acacia genus. In this study, the previously built Acacia database was expanded, principal component analysis (PCA) was used to aid in grouping of the samples, and data interpretation was refined following a modified acacieae taxonomy. Application of the analytical strategy to investigate the paint binders in artworks from ancient Egypt allowed qualitative discrimination of gums at a species level, and provided new insights into the artists' material choices.

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New insight from MALDI-TOF MS and multivariate data analysis on the botanical origin of polysaccharide-based paint binders in ancient Egypt

C. Granzotto, A. Aksamija, G. H. Tinnevelt, V. Turkina and K. Sutherland, Anal. Methods , 2024, Advance Article , DOI: 10.1039/D3AY02214E

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Column generation based solution for bi-objective gate assignment problems

• Original Article
• Published: 29 April 2024

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• Gülesin Sena Daş 1 , 2 &
• Fatma Gzara 3  

In this paper, we present a column generation-based algorithm for the bi-objective gate assignment problem (GAP) to generate gate schedules that minimize squared slack time at the gates while satisfying passenger expectations by minimizing their walking distance. While most of the literature focuses on heuristic or metaheuristic solutions for the bi-objective GAP, we propose flow-based and column-based models that lead to exact or near optimal solution approaches. The developed algorithm calculates a set of solutions to approximate the Pareto front. The algorithm is applied to the over-constrained GAP where gates are a limited resource and it is not possible to serve every flight using a gate. Our test cases are based on real data from an international airport and include various instances with flight-to-gate ratios between 23.9 and 34.7. Numerical results reveal that a set of solutions representing a compromise between the passenger-oriented and robustness-oriented objectives may be obtained with a tight optimality gap and within reasonable computational time even for these difficult problems.

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Barnhart C, Boland NL, Clarke LW, Johnson EL, Nemhauser GL, Shenoi RG (1998) Flight string models for aircraft fleeting and routing. Transp Sci 32(3):208–220

Article   Google Scholar  

Benlic U, Burke EK, Woodward JR (2017) Breakout local search for the multi-objective gate allocation problem. Comput Oper Res 78:80–93

Article   MathSciNet   Google Scholar  

Bihr RA (1990) A conceptual solution to the aircraft gate assignment problem using 0, 1 linear programming. Comput Ind Eng 19(1):280–284

Braaksma JP, Shortreed JH (1971) Improving airport gate usage with critical path. Transp Eng J ASCE 97(2):187–203

Cai X, Sun W, Misir M, Tan KC, Li X, Xu T, Fan Z (2019) A bi-objective constrained robust gate assignment problem: formulation, instances and algorithm. IEEE Trans Cybern 51(9):4488–4500

Cecen RK (2021) Multi-objective optimization model for airport gate assignment problem. Aircraft Eng Aerosp Technol 93:311

Cheng Y (1997) A knowledge-based airport gate assignment system integrated with mathematical programming. Comput Ind Eng 32(4):837–852

Daş GS (2017) New multi objective models for the gate assignment problem. Comput Ind Eng 109:347–356

Daş GS, Gzara F, Stützle T (2020) A review on airport gate assignment problems: single versus multi objective approaches. Omega 92:102146

Dell’Orco M, Marinelli M, Altieri MG (2017) Solving the gate assignment problem through the fuzzy bee colony optimization. Transp Res Part C Emerg Technol 80:424–438

Deng W, Zhao H, Yang X, Xiong J, Sun M, Li B (2017) Study on an improved adaptive PSO algorithm for solving multi-objective gate assignment. Appl Soft Comput 59:288–302

Diepen G, Van Den Akker JM, Hoogeveen JA, Smeltink JW (2012) Finding a robust assignment of flights to gates at Amsterdam airport Schiphol. J Sched 15(6):703–715

Ding H, Lim A, Rodrigues B, Zhu Y (2005) The over-constrained airport gate assignment problem. Comput Oper Res 32(7):1867–1880

Dorndorf U, Jaehn F, Pesch E (2008) Modelling robust flight-gate scheduling as a clique partitioning problem. Transp Sci 42(3):292–301

Drexl A, Nikulin Y (2008) Multicriteria airport gate assignment and pareto simulated annealing. IIE Trans 40(4):385–397

Ehrgott M (2005) Multicriteria optimization, vol 491. Springer, New York

Google Scholar  

Ehrgott M, Gandibleux X, Przybylski A (2016) Exact methods for multi-objective combinatorial optimisation. In: Figueira J, Greco S, Ehrgott M (eds) Multiple criteria decision analysis, vol 233. Springer, New York, pp 817–850

Chapter   Google Scholar  

Emmerich MT, Deutz AH (2018) A tutorial on multiobjective optimization: fundamentals and evolutionary methods. Nat Comput 17:585–609

Glize E, Jozefowiez N, Ngueveu SU (2018) An exact column generation-based algorithm for bi-objective vehicle routing problems. In: Mahjoub A, Lee J, Rinaldi G (eds) Combinatorial optimization. ISCO 2018, vol 10856. LNCS. Springer, Cham, pp 208–218

Grönkvist M (2006) Accelerating column generation for aircraft scheduling using constraint propagation. Comput Oper Res 33(10):2918–2934

Haghani A, Chen M-C (1998) Optimizing gate assignments at airport terminals. Transp Res Part A Policy Pract 32(6):437–454

Hu XB, Di Paolo E (2009) An efficient genetic algorithm with uniform crossover for the multi-objective airport gate assignment problem. Stud Comput Intell 171:71–89

Kaliszewski I, Miroforidis J, Stańczak JT (2017) Multiobjective optimization in the airport gate assignment problem, exact versus evolutionary multiobjective optimization. Comput Sci 18(1):41

Kaliszewski I, Miroforidis J (2019) Lower and upper bounds for the general multiobjective optimization problem. In: AIP conference proceedings, vol 2070. AIP Publishing LLC, p 020038

Karsu Ö, Azizoğlu M, Alanlı K (2021) Exact and heuristic solution approaches for the airport gate assignment problem. Omega 103:102422

Kim SH, Feron E, Clarke JP (2013) Gate assignment to minimize passenger transit time and aircraft taxi time. J Guid Control Dyn 36(2):467–475

Kim SH, Feron E, Clarke JP, Marzuoli A, Delahaye D (2017) Airport gate scheduling for passengers, aircraft, and operation. J Air Transp 25:1–6

Li Y, Clarke JP, Dey SS (2021) Using submodularity within column generation to solve the flight-to-gate assignment problem. Transp Res Part C Emerg Technol 129:103217

Lim A, Wang F (2005) Robust airport gate assignment. In: 17th IEEE international conference on tools with artificial intelligence, 2005. ICTA I . IEEE, pp 74–81

Lin KM, Ehrgott M, Raith A (2017) Integrating column generation in a method to compute a discrete representation of the nondominated set of multi-objective linear programmes. 4OR 15(4):331–357

Liu S, Chen WH, Liu J (2016) Robust assignment of airport gates with operational safety constraints. Int J Autom Comput 13(1):31–41

Maharjan B, Matis TI (2012) Multi-commodity flow network model of the flight gate assignment problem. Comput Ind Eng 63(4):1135–1144

Mangoubi RS, Mathaisel DFX (1985) Optimizing gate assignments at airport terminals. Transp Sci 19(2):173–188

Mavrotas G, Florios K (2013) An improved version of the augmented ε constraint method (AUGMECON2) for finding the exact pareto set in multi-objective integer programming problems. Appl Math Comput 219(18):9652–9669

MathSciNet   Google Scholar  

Mokhtarimousavi S, Talebi D, Asgari H (2018) A nondominated sorting genetic algorithm approach for optimization of multi-objective airport gate assignment problem. Transp Res Rec 2672:1–12

Moradi S, Raith A, Ehrgott M (2015) A bi-objective column generation algorithm for the multi-commodity minimum cost flow problem. Eur J Oper Res 244(2):369–378

Neuman UM, Atkin JA (2013) Airport gate assignment considering ground movement. In: International conference on computational logistics, pp 184–198

Nikulin Y, Drexl A (2010) Theoretical aspects of multicriteria flight gate scheduling: deterministic and fuzzy models. J Sched 13(3):261–280

Nourmohammadzadeh A, Voß S (2021) Robust multi-objective gate scheduling at hub airports considering flight delays: a hybrid metaheuristic approach. In: International conference on computational logistics. Springer, pp 594–610

Pintea C-M, Pop PC, Chira C, Dumitrescu D (2008) A hybrid ant-based system for gate assignment problem. In: Hybrid artificial intelligence systems, pp 273–280

Prem Kumar V, Bierlaire M (2014) Multi-objective airport gate assignment problem in planning and operations. J Adv Transp 48(7):902–926

Ruzika S, Wiecek MM (2005) Approximation methods in multiobjective programming. J Optim Theory Appl 126(3):473–501

Şeker M, Noyan N (2012) Stochastic optimization models for the airport gate assignment problem. Transp Res Part E Logist Transp Rev 48(2):438–459

Tang C-H, Wang W-C (2013) Airport gate assignments for airlinespecific gates. J Air Transp Manag 30:10–16

Xu J, Bailey G (2001) The airport gate assignment problem: mathematical model and a tabu search algorithm. In: Proceedings o f the 34th annual hawaii international conference on system sciences. IEEE

Yan S, Chang CM (1998) A network model for gate assignment. J Adv Transp 32(2):176–189

Yan S, Huo CM (2001) Optimization of multiple objective gate assignments. Transp Res Part A Policy Pract 35(5):413–432

Yildiz BC, Gzara F, Elhedhli S (2017) Airline crew pairing with fatigue: modeling and analysis. Transp Res Part C Emerg Technol 74:99–112

Yu C, Zhang D, Lau HYK (2016) MIP-based heuristics for solving robust gate assignment problems. Comput Ind Eng 93:171–191

Yu C, Zhang D, Lau HYK (2017) An adaptive large neighborhood search heuristic for solving a robust gate assignment problem. Expert Syst Appl 84:143–154

Yuan Y, Yan P, Zhao L (2020) Continuous time formulation and Lagrangian relaxation algorithm for the gate assignment problem. Math Probl Eng 2020:1–11

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The first author is supported by Scientific and Technological Research Council of Turkey (TUBITAK) (Grant No. 1059B191700275) 2219 Post Doctoral Research Fellowship Program during her research at WAnOpt Lab, University of Waterloo.

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Department of Industrial Engineering, Kırıkkale University, Kırıkkale, Turkey

Gülesin Sena Daş

Leicester Castle Business School, De Montfort University, Leicester, UK

Department of Management Science and Engineering, University of Waterloo, Waterloo, ON, Canada

Fatma Gzara

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Daş, G.S., Gzara, F. Column generation based solution for bi-objective gate assignment problems. Math Meth Oper Res (2024). https://doi.org/10.1007/s00186-024-00856-1

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Received : 26 June 2022

Revised : 22 February 2024

Accepted : 03 March 2024

Published : 29 April 2024

DOI : https://doi.org/10.1007/s00186-024-00856-1

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