A scoping review of the problems and solutions associated with contamination in trials of complex interventions in mental health

摘要

BackgroundIn a randomised controlled trial, contamination is defined as the receipt of active intervention amongst participants in the control arm. This review assessed the processes leading to contamination, its typical quantity, methods used to mitigate it, and impact of use of cluster randomisation to prevent it on study findings in trials of complex interventions in mental health.