GalterGuides: Systematic Reviews: What is a Systematic Review?

What is a systematic review?

“A systematic review attempts to identify, appraise and synthesize all the empirical evidence that meets pre-specified eligibility criteria to answer a given research question. Researchers conducting systematic reviews use explicit methods aimed at minimizing bias, in order to produce more reliable findings that can be used to inform decision making.”

- About Cochrane Reviews, Cochrane Library

Review Types

Review Type	Typical Use	Important Notes
Systematic Review	Ask a specific research question Use pre-specified inclusion criteria Appraise and synthesize the evidence	Extended time commitment Should follow a prepared research protocol
Scoping Review	Ask a broader question Identify gaps Understand the size/reach of a topic	Extended time commitment Could involve multiple searches
Mapping Review	Categorize existing knowledge Identify gaps in literature Seeks to understand connections/links	Does not synthesize results/findings (categorizes)
Literature/Narrative Review	Summarize or comment on the literature	Varying levels of comprehensiveness
Umbrella Review	Review multiple high-level reviews Focus on competing interventions	Must include data synthesis Follows systematic review methods (only includes SRs & meta analyses)
Systematized Review	Uses elements of the systematic review process When resources are limited Used as a graduate assignment	May be limited in comprehensiveness Limited consideration of methodology
Critical Review	Extensive research and critical evaluation of a topic Looks for significant contributions	Typically has a narrative output Subjective output Launching point for further investigation

Chart adapted from: Grant MJ, Booth A. A typology of reviews: an analysis of 14 review types and associated methodologies. Health Info Libr J. 2009 Jun;26(2):91-108. doi: 10.1111/j.1471-1842.2009.00848.x.

Standards & Guidance

Here are some standards and additional research synthesis methods papers to get you started:

Higgins, J., Lasserson, T., Thomas, J., ... Churchill, R. (2023). Standards for the conduct of new Cochrane Intervention Reviews, and the planning and conduct of updates. Available from https://community.cochrane.org/mecir-manual .

Higgins, J., Green, S., & (editors). (2011). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated March 2011]. J. Higgins & S. Green (Eds.), Available from: http://handbook.cochrane.org/.

IOM (Institute of Medicine). (2011). Finding What Works in Health Care: Standards for Systematic Reviews. Available from: https://nap.nationalacademies.org/catalog/13059/finding-what-works-in-health-care-standards-for-systematic-reviews.

Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gotzsche, P. C., Ioannidis, J. P., . . . Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Medicine, 6(7), e1000100. doi: 10.1371/journal.pmed.1000100. Available from: http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1000100.

Moher, D., Liberati, A., Tetzlaff, J., Altman, D. G., & Prisma Group. (2009). Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Medicine, 6(7), e1000097. doi: 10.1371/journal.pmed.1000097. Available from: http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1000097.

Moher D., Shamseer L., Clarke M., Ghersi D., Liberati A., Petticrew M., . . . PRISMA-P Group (2015). Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Systematic Reviews, 4(1), doi:10.1186/2046-4053-4-1. Availalble from: http://systematicreviewsjournal.biomedcentral.com/articles/10.1186/2046-4053-4-1.

Rader, T., Mann, M., Stansfield, C., Cooper, C., & Sampson, M. (2013). Methods for documenting systematic review searches: a discussion of common issues. Research Synthesis Methods, Article first published online: 8 OCT 2013. doi: 10.1002/jrsm.1097. Available from: http://onlinelibrary.wiley.com/doi/10.1002/jrsm.1097/abstract.

Rethlefsen, M. L., Murad, M., & Livingston, E. H. (2014). Engaging medical librarians to improve the quality of review articles. JAMA, 312(10), 999-1000. doi: 10.1001/jama.2014.9263. Availalble from: http://jama.jamanetwork.com/article.aspx?articleid=1902238.

Shamseer, L., Moher, D., Clarke, M., Ghersi, D., Liberati, A. D., Petticrew, M., . . . PRISMA-P Group. (2015). Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015: elaboration and explanation. BMJ, 349, g7647. doi: 10.1136/bmj.g7647. Available from: http://www.bmj.com/content/349/bmj.g7647.long.

Umscheid, C. A. (2013). A Primer on Performing Systematic Reviews and Meta-analyses. Clinical Infectious Diseases, 57(5), 725-734. doi: 10.1093/cid/cit333. Available from: http://cid.oxfordjournals.org/content/57/5/725.long.