Risk of Bias 2 tool: the user's point of view
2Institute for Clinical Effectiveness and Health Policy (IECS), Argentina
Background: a few years ago, the Risk of Bias 2 tool (RoB2) appeared to replace the old RoB tool that has been used for years. As with any new tool, some authors were really adopters while others preferred to do it later when it was more 'probed'.
Objectives: We aimed to describe the workload of using RoB2 in a group of early adopters. Besides, we described some common questions and doubts that we, as an experimented team in systematic reviews, had during the process of risk bias assessment.
Methods: Two reviewers senior used RoB2 during the update of a Cochrane systematic review in the Cochrane GFG. We randomly selected 21 studies that had been included in the previous version of the review. We measured the time workload in each of the following steps during the assessment: before starting with the domains, each of the five RoB2 domains, and the overall analysis. We also performed a qualitative evaluation of the reasons why some domains took longer than others. And, finally, we described some of the questions that we made recurrently during the risk of bias assessment.
Results: The mean time of workload was 16.2 +- 4.7 minutes for each of the studies (range 10-26). Domain 2 was the one that took more time (4.7+- 2.1 minutes) while domain 5 was the shortest (1.2+-1.1).
Conclusions: RoB2 was easily adopted by this group of experienced reviewers. These results show that the evaluation may be more difficult for some domains than for others. A larger and more in-depth evaluation of this tool could be helpful to improve the feeling that both experienced and, especially, non-experienced reviewers could have when using RoB2.
Patient, public and/or healthcare consumer involvement: none.