Actuarial Assessment of Risk for Violence

Abstract

This article explores the predictive validity of two actuarial risk assessment instruments among mentally disordered offenders in Sweden: the historical part (H-10) of a historical, clinical, and risk management factors instrument (HCR-20) and the Violence Risk Appraisal Guide (VRAG). Actuarial scores were obtained retrospectively in two populations: one group of violent offenders with personality disorders and one with violent offenders diagnosed with schizophrenia. The predictive accuracy was evaluated with receiver operating characteristic analysis using a violent reconviction within 2 years from release or discharge as the criterion variable. Both scales fared better in the group of personality-disordered offenders than in the group of offenders with schizophrenia, and the H-10 fared better than the VRAG in both offender groups. The study found that historical data maintain a robust predictive validity in a population of personality-disordered offenders, whereas clinical and risk management factors may be of greater importance in offender populations in which major mental disorders are prevalent.