Addressing the Risk of Bias in Health Behaviour Change Trials: an Overview and Case Study


  • M. de Bruin
  • J. McCambridge
  • J.M. Prins


Objective: It has been suggested that health behaviour change (HBC) trials are less rigorously designed than –for example– drug trials. Is this due to poor trial design, incomplete trial reporting, or incompatibility between risk of bias assessment criteria and HBC trials? Design: An overview of the risk of bias literature is used as a framework against which the design process of a multi-site, cost-effectiveness trial of an HIV-treatment adherence intervention is compared (case study). Main Outcome Measures: Common risk of bias strategies that (1) could be implemented or (2)could not be implemented; (3)Alternative/additional strategies applied; (4) Arguments for discrepancies between the framework and case study. Results: Most of the common risk of bias strategies could be implemented. Alternative strategies were developed for minimizing the risk of performance bias and contamination. Several additional, trial-specific risk of bias strategies were identified. Conclusions: It seems that HBC trials can be developed more rigorously and reported more comprehensively. Yet, HBC trial designers may face specific challenges that require alternative/additional measures for reducing the risk of bias. Adoption of the approach presented by other HBC trial designers may contribute to better trial design, reporting and publication of the data required for tailoring risk of bias assessments to HBC trials.