[Risk assessment of sex offenders in a German-speaking sample. Applicability of PCL-SV, HCR-20+3, and SVR-20]

Regarding the relatively high relapse rates of sex offenders, an increasing need for forensic prognosis reports, doubts about their validity, and a continued lack of qualified forensic experts makes the supposedly simple application of instruments such as the Psychopathy Check List Screening Version (PCL-SV), HCR-20+3, or the Sexual Violence Risk 20 (SVR-20) very tempting. Those tools supply numeric values for quantifying assumed risk and have begun appearing more frequently in forensic reports. Their use for specific collectives without prior examination of accuracy, admissibility, and accountability may lead to serious mistakes and risks. This study by the Forensic Department of the Psychiatric University Hospital in Basel, Switzerland, is part of a larger cohort study on forensic risk assessment. It investigates among others the differential indication for PCL-SV, HCR-20+3, and SVR-20. In the present study, 64 sex offenders were retrospectively rated with these three instruments based on their respective reports for prior risk assessment, including criminal reports. Those ratings were then compared with prior results from the Structured Risk Assessment of Basel, as performed by the experts. Results of this study confirm the utility of PCL-SV, HCR-20+3 and SVR-20 in a German-speaking sample of sex offenders primarily as a scientific instrument. Beyond that, these instruments may also be used literally as a checklist. Their use for risk quantification should be limited primarily to the subgroup of antisocial and physically aggressive sex offenders.