In Cochrane reviews, risk of bias assessments for allocation concealment were frequently not in line with Cochrane's Handbook guidance

Ref ID 346
First Author I. Propadalo
Journal JOURNAL OF CLINICAL EPIDEMIOLOGY
Year Of Publishing 2019
URL https://www.jclinepi.com/article/S0895-4356(18)30625-5/fulltext
Keywords • General medical
• Risk of bias
• Cochrane
Problem(s) • Flawed risk of bias undertaken
• Weaknesses identified in some Cochrane reviews
Article Type Empirical
Article Subtype Cross-sectional survey/Methodological systematic review
First Author Country Croatia
Aim To assess whether the risk of bias judgments for allocation concealment in Cochrane systematic reviews, published from July 2015 to June 2016 in Cochrane Database of Systematic Reviews, were in line with recommendations from the Cochrane Handbook.
Level of Investigation Descriptive
Summary of Findings One-third (29%) of risk of bias judgments about allocation concealment in Cochrane reviews were discrepant from the Cochrane Handbook recommendations. Most discrepancies were made for trials where risk of bias was judged as low (92%). Cochrane authors used 66 categories of comments describing envelopes as a method of allocation concealment. In 66 envelope-related categories, describing risk of bias assessments from 15% of the analysed RCTs, most of the judgments were rated as low risk of bias, although only one of those categories is associated with low risk of bias according to the Cochrane Handbook.
Number of systematic reviews included 721
Number of eligible systematic reviews assessed 721
Treatment impacted No
Treatment impacted description
Interpretation impacted Not Applicable
Interpretation impacted description