Authors' reply

The implementation of a randomised controlled trial has its particular challenges, but so does changing clinical practice in and of itself. 4 As researchers, we may sometimes underestimate this gap between scientific evidence and the changes necessary in clinical practice for the implementation of evidence-based interventions. 2 Nicholls TL Brink J Desmarais SL Webster CD Martin ML The Short-Term Assessment of Risk and Treatability (START): a prospective validation study in a forensic psychiatric sample. 3 de Vogel V de Ruiter C van Beek D Mead G Predictive validity of the SVR-20 and Static-99 in a Dutch sample of treated sex offenders.