Evaluation of behavioural interventions in HIV/STI prevention.

There is an urgent need for well designed randomised trials to assess the impact of behavioural interventions at both individual and community levels in developed and developing countries. The relative lack of such studies partly reflects the particular challenges of applying randomised trials in this area. Although there are obvious differences between clinical and behavioural interventions, the principles underlying successful evaluation are not fundamentally different. Experience gained from clinical trial methodology over the past two decades should be applied and further developed to tackle the demands and challenges of evaluating behavioural interventions in HIV/STI prevention.