Skip to main content
U.S. flag

An official website of the United States government

On the Effectiveness of Sexual Offender Treatment in Prisons: A Comparison of Two Different Evaluation Designs in Routine Practice

Although there is less continuity of sexual offending in the life course than stereotypes suggest, treatment should lead to a further reduction of reoffending. Contrary to this aim, a recent large British study using propensity score matching (PSM) showed some negative effects of the core sex offender treatment program (SOTP) in prisons. International meta-analyses on the effects of sex offender treatment revealed that there is considerable variety in the results, and methodological aspects and the context play a significant role. Therefore, this study compared different designs in the evaluation of sex offender treatment in German prisons. PSM was compared with an exact matching (EM) by the Static-99 in a sample of 693 sex offenders from Bavarian prisons. Most results were similar for both methods and not significant due to low base rates. There was a treatment effect at p < .05 on general recidivism in the EM and at p = .06 on serious reoffending in the PSM. For sexual recidivism, EM showed a negative trend, whereas PSM suggested the opposite. Overall, the study underlines the need for more replications of evaluations of routine practice, methodological comparisons, sensitive outcome criteria, and differentiated policy information.

Categories and Services

Notice about external resources

These links are being provided as a convenience and for informational purposes only; they do not constitute an endorsement or an approval by the National Institute of Corrections (NIC) of any of the products, services or opinions of the corporation or organization or individual. NIC bears no responsibility for the accuracy, legality or content of the external site or for that of subsequent links. Contact the external site for answers to questions regarding its content.