Subject Guides

Systematic Review

A step by step guide

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 specific research question. Researchers conducting systematic reviews use explicit, systematic methods that are selected with a view aimed at minimizing bias, to produce more reliable findings to inform decision making."


Required elements of a Systematic Review:

  • A team to ensure unbiased screening
  • Conducted according to Cochrane OR JBI guidelines
  • Reported according to the PRISMA standards
  • File a protocol a priori
  • Reproducible and transparent search strategies of multiple applicable databases and  grey literature resources: PRISMA-S
  • Two phases of screening: Title/Abstract and Full Text by at least 2 screeners
  • Documentation of included and excluded studies according to the PRISMA flow diagram
  • Critical Appraisal of all included studies
  • Documentation of data extraction process per protocol
  • Citation of included studies, guidelines and tools utilized

The purpose of a systematic review is provide a synthesized, comprehensive view of the available literature on a specific topic. The systematic review methodology must be transparent, reproducible with strong validity and low risk of bias.  

Systematic Review Process Map

7 simplified steps to a systematic review

Systematic Review Timeline

With 5 team members, an average systematic review takes approximately 62 - 67 weeks (Borah, et. al. , 2016)

Getting started Assemble team and member roles, develop & refine research question, determine inclusion & exclusion criteria, acquire exemplar articles, meet with a librarian to develop search strategy, begin the protocol application 4-6 weeks
Primary search design Determine applicable databases, grey literature sources and develop pilot search strategy. Complete pilot screening process. Confirm changes for final search strategy 6-8 weeks
Finalize search design Adapt search strategy according to pilot screening feedback, peer review of finalized search strategy, run final search and begin title/abstract screening. 6-8 weeks
Screening Phase 1: Title and abstract screening. Phase 2: Full text screening    8-12 weeks
Critical appraisal  Appraise quantity of included studies 8-12 weeks
Data extraction  Based upon a priori protocol 8-12 weeks
Write the review Refer to reporting standards and guidelines: PRISMA 2020 8-12 weeks

This table is an estimate of time to complete based on a team of 4-6 FTE researchers working with an experienced librarian. 

Systematic Review Guidance

  • Aromataris E, Munn Z (Eds.). (2020). JBI Manual for Evidence Synthesis. Available from and
  • Campbell, M., McKenzie, J. E., Sowden, A., Katikireddi, S. V., Brennan, S. E., Ellis, S., … & Thomson, H. (2020). Synthesis without meta-analysis (SWiM) in systematic reviews: reporting guideline. BMJ, 368.
  • Higgins J.P.T., Thomas J., Chandler J., Cumpston M., Li T., Page M.J., Welch V.A. (Eds.). (2020 update). Cochrane Handbook for Systematic Reviews of Interventions version 6.1 (updated September 2020). Cochrane. 
  • Institute of Medicine (US) Committee on Standards for Systematic Reviews of Comparative Effectiveness Research, Eden, J., Levit, L., Berg, A., & Morton, S. (Eds.). (2011). Finding what works in health care: Standards for systematic reviews. National Academies Press (US).
  • Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., … & Moher, D. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ.