The following updates and corrections apply to version 5.1.0 of the Cochrane Handbook for Systematic Reviews of Interventions, and will be updated in the next published edition.
Section 4.3 Abstracts
Following an audit of abstracts by the Cochrane Editorial Unit in 2010/2011, a decision was made that abstracts could be up to 1000 words in length, though with a preference for them to be up to 700 words only. This change was implemented in RevMan in May 2011.
The following recommendation was included in the conduct standards as part of the Methodological Expectations for Cochrane Intervention Reviews (MECIR) project in October 2011, to ensure that the published review is as up to date as possible:
The search for studies should be updated for all relevant databases within six months before publication of the review or review update, and the results screened for potentially eligible studies.
Ideally the studies should be fully incorporated into the review. If not, then the potentially eligible studies will need to be reported, at a minimum as a reference under ‘Studies awaiting classification’ or ‘Ongoing studies’. The decision whether to incorporate any new studies fully into the review will need to be balanced against the delay in publication.
Section 7.6 Extracting data from reports
The following recommendation was included in the conduct standards as part of the Methodological Expectations for Cochrane Intervention Reviews (MECIR) project in October 2011:
Review authors should compare the magnitude and direction of effects reported by studies with how they are presented in the review, taking account of legitimate differences.
This is a reasonably straightforward way for authors to check a number of potential problems, including typographical errors in studies’ reports, accuracy of data collection and manipulation, and data entry into RevMan. For example, the direction of a standardized mean difference may accidentally be wrong in the review. A basic check is to ensure the same qualitative findings (e.g. direction of effect and statistical significance) between the data as presented in the review and the data as available from the original study. Results in forest plots should agree with data in the original report (point estimate and confidence interval) if the same effect measure and statistical model is used.