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Systematic Reviews

Information on how to conduct systematic reviews in the health sciences.

Systematic Review versus Literature Review Searches

Systematic Review

  Literature Review

Search strategies must be replicable

  • Document database names & platforms (Medline/Ovid, CINAHL/ EBSCO), search dates, all search terms & limits used in the methods section of a publication or in an appendix.
  • Informationists who create the search strategy often write the methods section.

Search strategies do not need to be replicable

  • Normally not published in the methods section.
  • Are less detailed when published.

Follow specific search methodologies that ensure comprehensive results

  • Search strategies are highly sensitive to find relevant articles.
  • Many databases are searched.
  • Other sources, such as & handsearching, are used.

Searches vary in how comprehensive      they are

  • Search strategies may not be as comprehensive in:
    • search terms used
    • the number of resources that searched.

Require a significant time commitment

  • Because of the methodology of systematic reviews, they can take 18-24 months to complete, even with a team involved.

Take much less time

  • The time frame depends on the topic, what you are trying to achieve with the search, & thus how comprehensive the search needs to be, but it can be significantly shorter.

Typically retrieve high number of results

  • Searches produce large numbers of search results because of the sensitivity of an SR search strategy.
  • Citations are excluded after manual review.

Retrieve lower number of results

  • These searches retrieve fewer results than SR search strategies because they are more specific than sensitive.
  • A manual review may not be necessary.

Require a team

  • Generally, two or more individuals independently review each article separately to determine whether it meets inclusion criteria.
  • Conflicts are solved by a third party. 

Can be completed by individuals

  • Results do not need to be reviewed for inclusion or exclusion by multiple individuals.


  • Answers a specific clinical question.
  • Has specific inclusion & exclusion criteria.
  • Uses methods for assessing bias.

Does not use a protocol


Adapted from Penn State Hershey


The types of review that you conduct depends on the type of project that you are doing. The chart on the right is a useful guide to differences between systematic reviews & literature reviews.

Types of Literature Reviews

If you are interested in learning more about the different types of literature reviews, consult this article, A typology of reviews: an analysis of 14 review types and associated methodologies, which defines 14 types of reviews.  There is a helpful summary table on pp. 94-95.

You can also use this handy tool to find the best  types of review to use:

A newer review type article:  Sutton A, Clowes M, Preston L, Booth A. Meeting the review family: exploring review types and associated information retrieval requirements. Health Info Libr J. 2019;36(3):202–222. doi:10.1111/hir.12276