Systematic Reviews

libguides.library.tmc.edu/SystematicReviews

A systematic review attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question.  It  uses explicit, systematic methods that are selected with a view to minimizing bias, thus providing more reliable findings from which conclusions can be drawn and decisions made.

The key characteristics of a systematic review are:

•      a clearly stated set of objectives with pre-defined eligibility criteria for studies
•       an explicit, reproducible methodology
•       a systematic search that attempts to identify all studies that would meet the eligibility criteria
•       an assessment of the validity of the findings of the included studies
•       a systematic presentation, and synthesis, of the characteristics and findings of the included studies

For a review to be called a ‘Cochrane Review’ it must be in Cochrane Database of Systematic Reviews or Cochrane Methodology Register. Cochrane Reviews are prepared using Review Manager (RevMan) software provided by the Cochrane Collaboration, and adhere to a structured format that is described in the Cochrane Handbook for Systematic Reviews of Interventions.

Meta-analysis is the use of statistical methods to summarize the results of independent studies. Many systematic reviews contain meta-analyses. By combining information from all relevant studies, meta-analyses can provide more precise estimates of the effects of health care than those derived from the individual studies included within a review. They also facilitate investigations of the consistency of evidence across studies, and the exploration of differences across studies.

References
Cochrane Handbook for Systematic Reviews of Interventions. Version 5.1.0. Updated March 2011. Section 1.2.2. 

Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, et al. (2009) The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration. PLoS Med 6(7): e1000100. doi:10.1371/journal.pmed.1000100

1. Put together an investigative team.
   · Generally, a team needs to have at least three people to reduce bias.
2. Develop a question – often clinical in nature.
3. Establish criteria for including and excluding studies.
4. Develop and register your protocol.
   · Check to see if there is not already a systematic review published or in progress on your topic.
   · Prospero and Cochrane are two sites that allow you to register your protocol.
5. Conduct an exhaustive literature search – often done by a professional, or a librarian.
   · Librarians should be considered a member of the team and receive authorship for their contributions. Librarians will often write or contribute to the Methods section.
6. Review results.
   · The review of articles should be a “blind” review, done by at least two individuals to reduce bias.
   · Journal Title and Author Name should be omitted from citations/articles for review.
7. Select and evaluate the articles/studies that meet inclusion.
8. Gather the evidence.
9. Come to conclusions.
10. Review work & run searches a last time to make sure you have recent publications.
11. Make corrections or changes as needed.
12. Submit work for publication.
    · The whole systematic review process on average takes at least 12 months.