The existing expectations for RoB 2 that were set out in November 2020 have been revisited and kept in place after results of a Cochrane-funded study were released. The study was initiated to underpin methods policy and implementation plans with data about the usability of RoB 2 compared with the study-based Cochrane risk of bias tool for RCTs, and its impact on efficiency and review quality. The work was led by Bernd Richter and Bianca Hemmingsen from the Cochrane Metabolic and Endocrine Disorders Group and looked at inter-reliability across domains, time-taken to perform assessments, usability issues, and consequences for analysis results and interpretation.

The decision to keep the current expectations in place means that uptake of RoB 2 to assess randomised controlled trials is encouraged but there will still be the option to use the study-based Cochrane risk of bias tool, providing it is applied in a way that allows for differences in bias across outcomes to be captured. Reviews using RoB 2 should be prepared and edited in RevMan Web to take advantage of functionality that has been designed to store and present assessments clearly. Authors wishing to adopt RoB 2 after the protocol has been published, including switching to the tool for a review update, should make the decision with editorial staff and consult the resources available in the Starter Pack for reporting guidance.

Related links:

• Full report of the study for more detail about how it was conducted and what it found
• Blog post discussing implications of the results of the RoB 2 comparison study for authors and editors  
• Blog post summarising important resources and practical guidance for RoB 2