Sexual offending is a public health issue and a social problem. Medical practitioners might assume from the volume of work published on treatments for sex offenders that clinically effective treatments are available. Indeed, psychological treatment is often mandated in the sentencing decision for sexual offenders. Yet the effectiveness of treatments is debated, and evidence for the efficacy of sex offender treatment programmes is often too readily accepted uncritically.1

In conducting a Cochrane meta-analysis on the effects of such psychological interventions we found nine trials that were well conducted in terms of randomisation, blinding, loss to follow-up, and analysis.2 These included randomised controlled trials with a total of 567 male offenders, 231 of whom were followed up for a decade.

The results indicated that studies on behavioural treatments were too small to be informative, although statistically significant improvements were recorded across some groups of offenders.2 Cognitive behavioural group therapy may reduce …