A typical question one may ask about sex offenders and treatment is: can sex offenders be "cured?" In general, those who treat sex offenders do not discuss them in terms of whether they can be "cured"—rather, they are discussed in terms of management. Similar to an alcoholic, who is not cured but rather can control his or her urges to consume alcohol, sex offenders are taught to resist the urges to commit a sex crime, and focus is placed on developing and maintaining healthy relationships.
Assessing effectiveness is difficult, given the necessary methodological criteria needed (e.g., lengthy follow-ups and control groups are required). Studies to assess treatment are often constrained by those who drop-out of treatment along with the problem that few sex offenders recidivate. Measuring recidivism is difficult, as many sex crimes go undetected. Despite these constraints, several meta-analyses have been conducted to determine the effectiveness of treatment for sex offenders.
It is no surprise that many may believe that sex offenders cannot be effectively treated—as the research in the 1990s reported just that. One meta-analysis conducted in 1995 (Hall, 1995) reported that those in treatment had higher sexual-recidivism rates than those not treated. Just a few years later, in 1999, another meta-analysis found that those treated were slightly less likely than those not treated to sexually recidivate (Alexander, 1999). Hanson et al. (2002), in a meta-analysis of 43 studies, found those treated recidivated less compared to those not treated. More specifically, 17.5% of those who did not receive treatment sexually recidivated, whereas 11.1% of those treated sexually recidivated. Thus, treatment led to an average of a 6% reduction in sexual recidivism.
More recently, Losel and Schmucker (2005) in their meta-analysis concluded that "the last decade has shown a strong increase and more positive outcomes in evaluations of sex offender treatment" (p. 119). In their meta-analysis involving 22,181 subjects, the treated offenders sexually recidivated 6% less than those not treated. While this may not seem like much of a difference, it translates into substantially less recidivism. A problem with sexual recidivism research is that so few of the offenders recidivate, often referred to as a low base-rate problem. Given that, one may ask what is the difference between 11.1% and 17.5%? The answer is that it means over a third (37%) fewer individuals in the treatment group committed a further sexual offense compared to the non-treatment group, a significant difference. With regard to sex-offender treatment, cognitive-behavioral programs currently have the best outcome.