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Systematic Reviews

This guide lists resources related to conducting 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.”

- Cochrane Library

When is a Systematic Review necessary?

Systematic reviews should be done:

  • When there is a large body of primary research on a specific research question
  • When a transparent search methodology and replicability are needed
  • When multiple published studies point to contradictory outcomes
  • When an existing systematic review is outdated (consider updating the existing review)
  • When no ongoing or existing systematic review addresses your research question. Try searching the following resources for protocols or completed systematic reviews before you get started:

Is a Systematic Review the right type of review for my research project?

What resources are needed to complete a Systematic Review?

Time: The length of time needed to complete a systematic review ranges from 6 months to 2 years, with an average mean project length of 67.3 weeks (Khangura et al., 2012; Borah et al., 2017)

Teamwork: A systematic review cannot be done alone. Results must be screened and appraised by a minimum of two reviewers, ideally  with a third available to settle any disagreements.

Tools: Access to a citation management tool with sharing capabilities (i.e. EndNote). 

What is the timeline for completing a Systematic Review?

Systematic reviews require a lot of time and effort to complete; a reasonable time frame is rarely under one year. The Cochrane Handbook for Systematic Reviews of Interventions suggests the following timeline to complete a Cochrane Review:

Month Activity
1 - 2 Preparation of protocol
3 - 8 Searches for published & unpublished studies
2 - 3 Pilot test of eligibility criteria
3 - 8 Inclusion assessments
3 Pilot test of 'Risk of bias' assessment
3 - 10 Validity assessments
3 Pilot test of data collection
3 - 10 Data collection
3 - 10 Data entry
5 - 11 Follow up of missing information
8 - 10 Analysis
1 - 11 Preparation of review report
12 - Keeping the review up to date


Creative Commons License

This guide was created by Ontario Tech Libraries and is licensed under a Creative Commons Attribution International 4.0 License, except where otherwise noted. 

Creative Commons Attribution International 4.0 License