Predicting Violent and Antisocial Behavior in Hospital Using the HCR-20: The Effect of Diagnoses on Predictive Accuracy

Before risk assessment instruments can be used to guide treatment, it is necessary to demonstrate accurate identification of patients at high risk for violence and of the factors associated with these behaviors for each individual. Predictors of violence vary by diagnosis, setting, and behavior being predicted. The present study examined violent and antisocial behavior of 216 patients in a forensic hospital during a one year period. The HCR-20 was completed by trained raters independent of those who collected information on antisocial and violent behavior. The HCR-20 predicted antisocial but not violent behavior. Different predictors were associated with different types of behaviors for different diagnostic groups. The HCR-20 score was highly positively correlated with patients' level of security.