Please note that your manuscript must include a 'Declarations' section including all of the subheadings (please see below for more information).
This should list the title of the article. The title should include the review question, for example: What is the effectiveness of intervention A in producing change in subject B? What is the impact of factor X on subject Y?
The title should also indicate that it is a systematic map, for example:
- What is the effectiveness of intervention A in producing change in subject B? A systematic map.
- What is the impact of factor X on subject Y? A systematic map.
The full names, institutional addresses, and email addresses for all authors must be included on the title page. The corresponding author should also be indicated.
The Abstract of the manuscript should not exceed 500 words and must be structured into the following separate sections: Background, the context and purpose of the review, including the review question; Methods, how the review was performed including brief overview of all methodological steps; Review findings, the main findings, including results of search and assessment of evidence base; Conclusions, brief summary and potential implications for policy/management and research.
Three to ten keywords representing the main content of the article should be given. Please avoid repeating words that are already in the title.
The Background section should be written in a way that is accessible to readers without specialist knowledge in that area and must clearly state - and, if helpful, illustrate - the background to the review and its aims. Reports should indicate why this study was necessary and what it aimed to contribute to the field. A theory of change and/or conceptual model should be presented that links the intervention or exposure to the outcome. The role of commissioners and other stakeholders in the formulation of the question should be described and explained. The section should end with a brief statement of what is being reported in the article. A clear reference should be made to the protocol and any differences between what was planned and what was conducted.
Objective of the Review
This section should describe the primary question and secondary questions when applicable. The primary question is the main question of the review. The secondary questions are usually linked to possible subgroup analyses. This section may also present definitions of the primary question components (e.g. the subject population, intervention and outcome measure) but see also ‘study eligibility criteria’ below.
This section should describe the design and conduct of the review. Although the methods may be somewhat repetitive of the protocol they should be given in full. Direct citation of the protocol should be made here. A clear description of all review stages should typically follow the format below;
Deviations from the protocol
Here describe any differences in methods to the ones proposed in the protocol including changes to searching, eligibility criteria and screening process, critical appraisal, data coding and synthesis. Please justify these changes.
Search for articles
Here all searches should be described in sufficient detail so as to be replicable. The following bullet points are a guide to the subsections and detail required in describing the search strategy, the sources searched and how the search was conducted, including limitations.
- Search terms and strings: How were decisions made and justified on the search terms and languages in which search was conducted? All search strings used for each of the searches conducted (including searches via search engines, publication databases and specialist websites) should be provided in a supplementary file. Search strings should be provided exactly as they were used, including combinations of terms using Boolean operators (AND, OR, NOT, etc.), wildcards (to include alternative forms of words, plurals, etc.) or any other special characters. Where searches could not be conducted using search strings, but individual search terms were used, those terms should also be listed. Trial development of search strings (if not included in the protocol) may also be included as an Additional File.
- Search limitations: State date ranges imposed on the search with justification. State all languages in which searches were conducted and any limitations this may impose on the review.
- Search sources: List all publication databases, citation indexes and other services that were searched, including details of institutional subscriptions used to access these services (or date ranges subscribed for each database searched), search options (e.g. ‘topic words’ or ‘full text’ search facility) and dates of searches.
- Search sources: List all search engines used, including a description of search options (e.g. title search) and dates of searches. Justify any strategy to limit the number of search results considered. Describe how you coped with limitations to using search strings if any.
- Search sources: Searches of organisational websites should be described, including a list of websites searches, dates of searches, any filtering or limitations applied.
- Supplementary searches: Supplementary searches should also be described so as to be replicable. These include Bibliographical searches, ‘snowballing’ or obtaining literature from experts or stakeholders (via open calls and similar).
- Estimating the comprehensiveness of the search: If not reported at the protocol stage, please state how you tested the comprehensiveness of your search. For example, did you compile a benchmark list of relevant studies to test the sensitivity of your searches?
- Search results: You may also describe how you assembled a library of search results i.e. how you combined and deduplicated search results and which reference (or review) management software you used to do this.
Article screening and study eligibility criteria
Describe the article screening process and decisions regarding eligibility, at title, abstract, full-text level. Describe how the consistency of eligibility decisions was measured and reported, and how disagreements between reviewers were resolved so as to inform subsequent decisions.
Confirm the exclusion of the review team member (who have also authored articles considered within the review) from decisions regarding inclusion or study validity assessment of their own work.
Eligibility criteria should be precisely defined (e.g. reliance on broad and potentially ambiguous terms should be avoided) and expressly related to each key element of the question. Here describe criteria and definitions followed to include eligible articles so that this stage is transparent and replicable. You may add examples of both eligible and ineligible articles to clarify the criteria. Organise this section according to following subsections (or equivalent for other question types):
- Eligible population(s) or subject(s)
- Eligible intervention(s) or exposure(s)
- Eligible comparator(s) (if appropriate)
- Eligible outcomes
- Eligible types of study design
- Any additional criteria
Study validity assessment
If study validity assessment was undertaken, describe how you attempted a preliminary assessment of the validity of included studies. This may be a report of the design of each study or an assessment of internal validity (risk of bias). Report any checklists used. Describe how the information from this assessment was used in synthesis and how repeatability of critical appraisal of study validity was tested.
Data coding strategy
State what categories of meta-data were intended to be coded. Describe here the methods by which meta-data from each study were extracted so that the process can be replicated. Specifically, state how meta-data from included studies were recorded. Provide any spreadsheets (codebooks and data coding forms) used. State how you tested the consistency of the data coding process among reviewers. Describe any process for obtaining and confirming missing or unclear information or data from authors of studies included in this process.
Data mapping method
Describe here how you collated studies in order to present them as a map. Describe the methods used to identify and/or prioritise key knowledge gaps (unrepresented or underrepresented subtopics that warrant further primary research) and knowledge clusters (well-represented subtopics that are amenable to full synthesis via systematic review).
Findings of each stage of the map (e.g. search statistics, eligibility, critical appraisal) should be clearly reported. A narrative synthesis of included studies (usually in tabular form) may be presented (can be as additional material when appropriate). Subsections should follow the format:
Review descriptive statistics (sub-headings as applicable)
Report here the number of articles and the studies therein found in the search. A flow diagram reporting all stages of the inclusion/exclusion process, from search results to full text eligibility, should be presented. Results of consistency checking at all stages must be provided.
Descriptive statistics should be provided on any relevant information on the distribution of the articles found (e.g. geographical, temporal, institutional) in order to assess potential gaps or bias in the evidence. For full transparency, additional files are expected here including:
Tables of search results showing where eligible articles were found (i.e. through which database etc)A full reference list of all eligible articles A list of studies excluded at full text together with reasons for exclusion (reasons for exclusion should match your eligibility criteria).
Mapping the quantity of studies relevant to the question
Present here a figure or a database, showing how the relevant literature is organised (categories, coding...) according to transparent, replicable criteria. This map should be readily updatable.
Mapping the quality of studies relevant to the question
The map should provide some preliminary estimate of the quality of the available evidence. This may involve providing a description of the design of each study (or of a representative sample of studies).
This section should include an explanation of how the map can be used to find appropriate studies and observations on the distribution of articles and relative quantity and quality of available evidence with respect to the broad question and how the question might be broken down to enable full systematic review(s) to be conducted in future. Describe knowledge gaps (unrepresented or underrepresented subtopics that warrant further primary research) and knowledge clusters (well-represented subtopics that are amenable to full synthesis via systematic review)
Limitations of the map
A detailed and reflective discussion of the limitations of the review is expected here, including limitations due to the search strategy (limitations of the review methods), as well as limitations due to underlying bias within the studies found such as baseline bias and confounding variables (limitations of the evidence base). Please do not provide a discussion section that includes speculation or expert opinion concerning the review findings.
This section should be divided into:
Implication for Policy/Management
This section summarises the state of the evidence base in terms of the distribution and abundance of studies captured in the map in relation to different elements of the question. Potential for unpacking the broad question and enabling more detailed evidence synthesis should be highlighted. The intention is to inform and any form of advocacy should be excluded.
Implication for Research
This section summarises the shortcomings of the current evidence base in terms of knowledge gaps and the need for primary research. In this section some advocacy for research is permissible provided it is clearly justified by the review outcome. This should take the form of recommendations for future study designs that would improve the evidence base.