Systematic review and evidence synthesis

Librarians partner with researchers to conduct evidence syntheses. These are syntheses of all previously conducted research on a topic and represent the highest level of evidence in research. The service is available to U of M researchers.

About the service

Evidence synthesis reviews encompass systematic reviews, scoping reviews, meta-analyses, and evidence gap maps, and more. Unlike other types of reviews, these research methods include a reproducible and transparent methodology. For help differentiating between the various types of review, consult A Typology of Reviews (Grant & Booth, 2009).

Work with librarians to increase the quality of reviews and streamline the process. Librarians help you:

  • determine if there are existing reviews on your topic,  
  • develop a protocol to ensure transparency and rigor,
  • create search strategies to identify all relevant studies,
  • deliver search results formatted for citation managers and evidence synthesis review tools,
  • implement best practices for screening, risk of bias assessment, and data extraction and synthesis,
  • write the search methodology, and
  • determine best evidence synthesis type for your project.

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How librarians can help

As you start your evidence synthesis project, librarians can help at either the consultant or co-author level.


As a consultant, a librarian can step in at different points of your evidence synthesis review. Librarians can

  • provide background information and resources on the evidence synthesis process,
  • recommend databases, protocol registration platforms, and citation management software, and
  • suggest edits for your search strategy.

This option is a limited time commitment.


Co-authoring is a more substantial commitment, and a librarian will typically devote more than a year to partner with you on your evidence synthesis review.

As a co-author, the librarian will be more hands-on and can

  • comment on the protocol,
  • select databases and grey literature resources,
  • write the search strategy,
  • translate searches to syntax of all databases,
  • perform searches and export them to citation management software,
  • perform deduplication, or train your team on the process,
  • set up in article screening software, and
  • write a portion of the methods section specific to searching.

Request a review

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Tasks and timelines

An evidence synthesis review will typically require a year or more to complete, and librarians’ availability may vary, so please plan ahead and reach out to us as early as you can.

Below is a detailed chart that breaks down the steps of a traditional evidence synthesis review and the librarian co-author’s potential contributions.

Note: these time estimates may vary depending on the project, and some steps may happen concurrently.

Steps in a traditional evidence synthesis review Estimated time investment Potential contribution of librarian co-author
1. Assemble evidence synthesis review team and select project manager Varies Provide guidance
2. Identify appropriate review methodology 2 weeks Provide guidance
3. Define research question 2 weeks Provide information on appropriate question frameworks (e.g. PICO)
4. Define inclusion/exclusion criteria 1 week Provide guidance
5. Select databases 1 week Suggest appropriate databases
6. Select grey literature resources 1 week Suggest grey literature resources
7. Write search strategy for primary database 2-4 weeks Lead writing of the search strategy
8. Write and register protocol (written compilation of previous steps) Varies Provide comments on protocol and guide protocol registration process
9. Translate search strategy to syntax 2 of all databases (including grey literature) 2-4 weeks Translate search strategy
10. Search and export results into citation management software 2 weeks Perform searches and export results
11. De-duplicate results 2-4 weeks Perform de-duplication, or train your team on the process
12. Title and abstract screening 2–3 months* Recommend article screening software and advise on use of software
13. Retrieve full-text articles 1 month* Train team on full-text article retrieval
14. Full-text screening 2–3 months* Provide guidance
15. Risk-of-bias assessment 2–3 months Provide guidance
16. Data extraction 2–3 months Provide guidance
17. Meta-analysis or synthesis of results 2–3 months Provide guidance
18. Write the manuscript 2–3 months Write information retrieval portion of the methods section

* Timeframe can vary significantly depending on number of citations identified for screening.

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