Background: The reviewers recognise that it may be thought that convicted sex offenders and those with disorders of sexual preference are quite different groups. In combining them within this review we have taken the view that legal process alone should not define the population. Illegal behaviours in one jurisdiction may not be considered so in others. Studies of those who are convicted of sexual offending describe reconviction rates for sexual offences of up to 40-60%. It would seem important to know if there are interventions that might reduce this high rate of re-offending. This review examines antilibidinal management of those who have been convicted of sexual offences or who have disorders of sexual preference.
Objectives: To determine the effectiveness of a range of management techniques to assist people who have disorders of sexual preference and those who have been convicted of sexual offences.
Search strategy: Biological Abstracts, the Cochrane Schizophrenia Group Register of Trials, The Cochrane Library, EMBASE, MEDLINE, and PsychLIT were searched. Further references were sought from published trials and their authors. Relevant pharmaceutical manufacturers were contacted.
Selection criteria: All relevant randomised controlled trials.
Data collection and analysis: Reviewers evaluated data independently and analysed on an intention-to-treat basis. Data were extracted for short and medium term outcomes.
Main results: A single trial (McConaghy 1988) found the effect of antilibidinal medication (medroxyprogesterone acetate) plus imaginal desensitisation was no better than imaginal desensitisation for problematic/anomalous sexual behaviour and desire. A relapse prevention programme was trialed by Marques (Marques 1994) and participants were followed up for an average of 3 years. What data there are suggest that although there is no discernable effect on the outcome of sex offending (OR 0.76 CI 0. 26-2.28) those treated with response prevention do have less non-sexual violent offences (OR 0.3, CI 0.1-0.89, NNT 10 CI 5-85). In addition those committing both sexual and violent offences also declined in the response prevention group (OR 0.14 CI 0.02-0.98, NNT 20 CI 10-437). A large pragmatic trial investigated the value of group therapy for sex offenders (Romero 1983). This study finds no effect on recidivism at ten years.
Reviewer's conclusions: It is disappointing to find that this area lacks a strong evidence base, particularly in light of the controversial nature of the treatment and the high levels of interest in the area. The relapse prevention programme did seem to have some effect on violent reoffending but large, well-conducted randomised trials of long duration are essential if the effectiveness or otherwise of these treatments are to be established.