BACKGROUND: Risk assessment instruments have become a preferred means for predicting future aggression, claiming to predict long-term aggression risk. AIMS: To investigate the predictive value over 12 months and 4 years of two commonly applied instruments (Historical, Clinical and Risk Management - 20 (HCR-20) and Violence Risk Appraisal Guide (VRAG)).
METHOD: Participants were adult male psychiatric patients detained in a high secure hospital. All had a diagnosis of personality disorder. The focus was on aggression in hospital.
RESULTS: The actuarial risk assessment (VRAG) was generally performing better than the structured risk assessment (HCR-20), although neither approach performed particularly well overall. Any value in their predictive potential appeared focused on the longer time period under study (4 years) and was specific to certain types of aggression.