A systematic review is “…a review of a clearly formulated question that uses systematic and explicit methods to identify, select and critically appraise relevant research, and to collect and analyze data from the studies that are included in the review.” (Cochrane Handbook) Combing the results of several studies "gives a more reliable and precise estimate of an intervention’s effectiveness than one study alone." (Centre for Reviews and Dissemination)
Systematic reviews differ from narrative reviews, which are often authored by experts in a field and are generally narrative summaries of a topic.
The Systematic Review Process
This 30 minute video will walk you through the process of conducting a systematic review.
Estimated timeline for completing a Cochrane systematic review
1 – 2 Preparation of protocol.
3 – 8 Searches for published and unpublished studies.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.
Source: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated March 2011]. The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.