Risk of Bias in HIV-treatment Adherence Intervention Trials: a Systematic Review and Meta-analysis of Rcts

Abstract

Background: More needs to be understood regarding the extent to which risk of bias exists and how this may affect intervention effects reported in reviews of health behaviour interventions. This paper examines risk of bias in HIV medication adherence (MA) intervention trials. Methods: Databases were systematically searched for RCTs published between 1996 and 2012. Data was abstracted for study characteristics, quality of study methodology to assess risk of bias, and intervention effect estimates for adherence and viral load. A meta-analysis was conducted to assess the relationship between these variables. Results: 80 RCTs were obtained and coded. There was substantial risk of bias due to use of subjective behavioural measures, and inadequate and inaccurate reporting of random sequence generation, allocation concealment, and the intent-to-treat analysis. Risk of bias did not impact intervention effect estimates for HIV viral load, but did influence effect sizes for adherence behaviours. Conclusions: Improving the design of HIV MA trials and the comprehensiveness of trial design reports is needed to improve the quality of the evidence in MA trials.