Predicting Reoffence in Sexual Offender Subtypes: A Prospective Validation Study of the German Version of the Sexual Offender Risk Appraisal Guide (SORAG)

This study is part of a prospective, longitudinal research project to evaluate the reliability and validity of different recidivism risk assessment methods for sexual offenders under community supervision for scientific and practical use in the German-speaking part of Europe. In this paper we present the German adaptation of the Sexual Offender Risk Appraisal Guide (SORAG), a specific risk assessment tool for sexual offenders that was developed and published in 1998 in Canada. We examined interrater reliability, concurrent validity and predictive validity of the German version of the instrument with a sample of 254 male sexual offenders arrested in the Austrian penal system. The German SORAG showed good results for interrater reliability and concurrent validity. The predictive validity was determined using subgroups of the sample based on each offender’s index offence. The results were predominantly good, but the ability of the instrument to predict sexual and violent recidivism varied depending on offender type. The best results could be obtained for the prediction of re-imprisonment. The conclusion of this study is that the German version of the SORAG performs equally well and is most useful in predicting serious reoffenses.