Violence risk assessment and facet 4 of the Psychopathy Checklist: predicting institutional and community aggression in two forensic samples.

The Psychopathy Checklist and Psychopathy Checklist-Revised (PCL/PCL-R) were used to predict institutional aggression and community violence in two groups of forensic patients. Results showed that Facet 4 (Antisocial) of the PCL/PCL-R or one of its parcels consistently achieved incremental validity relative to the first three facets, whereas the first three facets failed to achieve incremental validity relative to Facet 4. One of the two Facet 4 parcels, Parcel G (General Acting Out), was the only PCL-R measure to consistently achieve success in classifying individual cases using the receiver operating characteristic approach. These findings suggest that Facet 4 and its parcels may play a role in violence risk assessment, although the generalizability of these findings to various forensic settings and contexts requires further study.