Predictive Properties and Factor Structure of the VRS-SO in an Austrian Sample

Abstract. We examined the structural and predictive properties of the Violence Risk Scale-Sexual Offense (VRS-SO) version in an Austrian sample of N = 666 men incarcerated for sexual offenses; 353 of whom were followed up an average of 11 years post-release. Results of a confirmatory factor analysis of dynamic item scores supported a three-factor model (Sexual Deviance, Criminality, and Treatment Responsivity) consistent with prior research. VRS-SO static, dynamic, and total scores showed good properties of discrimination for sexual (area under the receiver operating curve [AUC] = .68–.80) and violent (AUC = .65–.68) recidivism, while the factor scores showed differential prediction of these outcomes. Calibration analyses demonstrated lower estimated rates of 5-year sexual reoffense associated with VRS-SO score bands in the present sample compared to observed rates from the normative sample, with closest correspondence observed for the highest risk band (E/O index = 1.01). Implications for the psychometric properties and application of the VRS-SO in international settings are discussed.