These videos, originally part of the RoB 2: Learning Live webinar series, explain how to use the second domain of the RoB 2: bias due to deviations from the intended interventions. The presenters explain the difference between the effect of assignment to the intervention at baseline and the effect of adhering to the intervention as specified in the trial protocol, and also review the signalling questions within the domain and how to answer them. They then show the algorithm for how answers to signalling questions are mapped to judgements about risk of bias for the domains, along with worked examples. 

This session was intended for people who are interested in using RoB 2 to assess risk of bias in their review. In addition to review author teams, CRG editors can learn about the risk of bias due to deviations from the intended interventions so that they are able to assist authors with any queries they may have and also ensure information included in the review for this domain are relevant.

The webinar was delivered in July 2020 and below you will find the videos from the webinar, together with accompanying slides to download [PDF].

Part 1: Deviations from intended intervention and the role of blinding
Part 2: Effects of interest
Part 3: Risk of bias in the effect of assignment to intervention
Part 4: Risk of bias in the effect of adhering to intervention

Presenter Bios

Julian Higgins is Professor of Evidence Synthesis in the University of Bristol’s Department of Population Health Sciences where he is head of the Bristol Appraisal and Review of Research (BARR) group. His research interests span all areas of systematic review and meta-analysis. Among his methods contributions are: a Bayesian approach to network meta-analysis; the I-squared statistic to quantify inconsistency across studies in a meta-analysis; simple prediction intervals for random-effects meta-analysis; a general framework for individual participant data meta-analysis; a library of prior distributions for between-study variation in a meta-analysis; and risk-of-bias assessment tools for clinical trials and other study designs. He has long been an active contributor to Cochrane, is a former member of the Cochrane Collaboration Steering Group, the Cochrane Editorial Board and the Cochrane Scientific Committee, and is currently co-convenor of the Cochrane Bias Methods Group. He has co-edited the Cochrane Handbook for Systematic Reviews of Interventions since 2003.

Jonathan Sterne is Professor of Medical Statistics and Epidemiology in the University of Bristol’s Department of Population Health Sciences, and Deputy Director of the NIHR Bristol Biomedical Research Centre. He has a longstanding interest in methodology for systematic reviews and meta-analysis, led development of the ROBINS-I tool for assessing risk of bias in non-randomised studies of interventions, and co-leads development of version 2 of the Cochrane risk of bias tool for randomised trials. He leads a large-scale collaboration of HIV cohort studies that led to advances in our understanding of prognosis of HIV positive people in the era of effective antiretroviral therapy. Jonathan is a former co-convenor of the Cochrane Bias Methods Group. He has published influential papers on reporting bias in meta-analysis, meta-epidemiology, causal inference and statistical methodology.

Part 1: Deviations from intended intervention and the role of blinding

Part 2: Effects of interest

Part 3: Risk of bias in the effect of assignment to intervention

Part 4: Risk of bias in the effect of adhering to intervention

Additional materials

Download the slides from the webinar [PDF]