Adopted by the ATSA Executive Board of Directors on August 17, 2010

The Association for the Treatment of Sexual Abusers (ATSA) is committed to promoting evidence-based practices and high quality research. Consistent with professional and scientific opinion in diverse fields, ATSA recognizes randomized clinical trials (RCT’s) as the preferred method of controlling for bias in treatment outcome evaluations. ATSA promotes the use of RCT to distinguish between interventions that decrease the recidivism risk of sexual offenders and those programs that have no effect or are actually harmful.

Meta-analyses of studies of sex offender treatment have yielded some evidence of treatment efficacy. A study supported by ATSA (Hanson et al., 2002) and other large, comprehensive reviews (Hanson, Bourgon, Helmus & Hodgson, 2009; Lösel & Schmucker, 2005) have concluded that treatment can be effective with a difference in recidivism rates between treated and untreated offenders of up to 20%. On the other hand, the only random-assignment study of adult offenders that used a currently-recommended (cognitive-behavioural) treatment found no evidence of reduced recidivism among treated offenders (Marques, Wiederanders, Day, Nelson, & van Ommeren, 2005). After fifty years, the field of sex offender treatment cannot, using generally accepted scientific standards, demonstrate conclusively that effective treatments are available for adult sex offenders.

By contrast, evidence regarding interventions targeting juveniles and younger children is on much more solid ground, due to the use of studies with randomization. There have now been three published randomized clinical trials examining interventions targeting juvenile sexual offending (Borduin, Henggeler, Blaske, & Stein, 1990; Borduin, Schaeffer, & Heiblum, 2009; Letourneau et al., 2009) and six published randomized clinical trials examining interventions targeting child sexual behaviour problems with or without child sexual abuse (Berliner & Saunders, 1996; Bonner, Walker & Berliner, 1999; Cohen, Deblinger, Mannarino, & Steer, 2004; Cohen & Mannarino, 1998; Cohen & Mannarino, 1996; Deblinger, Satuffer & Steer, 2001). Not only do these RCTs provide evidence for treatment model effects on recidivism, but also have contributed data for nuanced assessments that have identified mediators and practice elements that contribute to treatment outcomes. These studies demonstrate that RCTs are achievable, and can make important contributions to knowledge concerning sexual offender treatment.

No study, including an RCT, is immune to methodological problems, such as sample representativeness and heterogeneity, inadvertent group non-equivalence in risk for recidivism or other factors that might moderate treatment outcome. Although modified, partial RCT designs have been proposed when a strong RCT design is not feasible, full RCTs are always preferable, and are unparalleled for determining causal relationships between treatment and outcome.

ATSA believes that RCT can and should be implemented in ways that respect the highest ethical standards. Community safety is better promoted by identifying treatments with strong evidence of effectiveness than by a proliferation of programs for which the efficacy is debatable.

Please refer to the ATSA Position Statement Recommendations for Implementation of Randomized Clinical Trial Design for further information.


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