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Systematic Reviews: Updating systematic reviews

New guidance on updating systematic reviews

When and how to update systematic reviews: consensus and checklist

BMJ 2016354 doi: https://doi.org/10.1136/bmj.i3507 (Published 20 July 2016)

Summary points

Updating systematic reviews is, in general, more efficient than starting afresh when new evidence emerges. The panel for updating guidance for systematic reviews (PUGs; comprising review authors, editors, statisticians, information specialists, related methodologists, and guideline developers) met to develop guidance for people considering updating systematic reviews. The panel proposed the following:

  1. Decisions about whether and when to update a systematic review are judgments made for individual reviews at a particular time. These decisions can be made by agencies responsible for systematic review portfolios, journal editors with systematic review update services, or author teams considering embarking on an update of a review.

  2. The decision needs to take into account whether the review addresses a current question, uses valid methods, and is well conducted; and whether there are new relevant methods, new studies, or new information on existing included studies. Given this information, the agency, editors, or authors need to judge whether the update will influence the review findings or credibility sufficiently to justify the effort in updating it.

  3. Review authors and commissioners can use a decision framework and checklist to navigate and report these decisions with “update status” and rationale for this status. The panel noted that the incorporation of new synthesis methods (such as Grading of Recommendations Assessment, Development and Evaluation (GRADE)) is also often likely to improve the quality of the analysis and the clarity of the findings.

  4. Given a decision to update, the process needs to start with an appraisal and revision of the background, question, inclusion criteria, and methods of the existing review.

  5. Search strategies should be refined, taking into account changes in the question or inclusion criteria. An analysis of yield from the previous edition, in relation to databases searched, terms, and languages can make searches more specific and efficient.

  6. In many instances, an update represents a new edition of the review, and authorship of the new version needs to follow criteria of the International Committee of Medical Journal Editors (ICMJE). New approaches to publishing licences could help new authors build on and re-use the previous edition while giving appropriate credit to the previous authors.

The panel also reflected on this guidance in the context of emerging technological advances in software, information retrieval, and electronic linkage and mining. With good synthesis and technology partnerships, these advances could revolutionise the efficiency of updating in the coming years.

Updating systematic reviews

The challenges (Lefebvre C et al) “associated with updating reviews may be mitigated to some extent by techniques such as searches based on previously ‘included’ studies (for example, citation searches of the ‘largest’/‘newest’ studies (Sampson, M et al) and ‘horizon-scanning’ for ‘trials that would make a difference’” (Shekelle, PG et al):

Methodological developments in searching for studies for systematic reviews: past, present and future?

Lefebvre C, Glanville J, Wieland LS, Coles B, Weightman AL.

Syst Rev. 2013 Sep 25;2:78. doi: 10.1186/2046-4053-2-78.

Surveillance search techniques identified the need to update systematic reviews.

Sampson M, Shojania KG, McGowan J, Daniel R, Rader T, Iansavichene AE, Ji J, Ansari MT, Moher D.

J Clin Epidemiol. 2008 Aug;61(8):755-62. doi: 10.1016/j.jclinepi.2007.10.003. Epub 2008 Feb 14.

Identifying Signals for Updating Systematic Reviews: A Comparison of Two Methods [Internet].

Shekelle PG, Newberry SJ, Wu H, Suttorp M, Motala A, Lim YW, Balk EM, Chung M, Yu WW, Lee J, Gaylor JM, Moher D, Ansari MT, Skidmore R, Garritty C.

Rockville (MD): Agency for Healthcare Research and Quality (US); 2011 Jun.