Cluster analysis of a forensic population with antisocial personality disorder regarding PCL-R scores: differentiation of two patterns of criminal profiles

Fifty six cases of a forensic population were submitted to a cluster analysis to observe the aglomerative behavior in relation to the total scores of the items comprising the PCL-R Psychopathy Checklist Revised [R.D. Hare, Manual for the Hare Psychopathy Checklist-Revised, Multi-Health System, Toronto, 1991]. The analysis indicated two independent types of antisocial personality disorders, not identified in the PCL-R in its standardized form, one of them being strongly associated with criminal conduct and the other with psychopathic personality. Such clusters were stable when the analysis was replicated with other hierarchical algorithms, and also, they were independently extracted via the k-means method without having previously fixed the value for k. One of the clusters concentrated the PCL-R highest scores, indicating that it is the prototypical psychopathic character determinant.     

Identifying the cutoff score for the PCL-R scale (psychopathy checklist-revised) in a Brazilian forensic population

This study introduces a Portuguese-language version of psychopathy checklist-revised (PCL-R) [Harv. Mental Health Lett. 12 (1995) 4] in the Brazilian penitentiary system. Hare's scale is used extensively in many other countries. In a forensic population sample of 56 male subjects classified as psychopaths and non-psychopaths [Manual for the Hare Psychopathy Checklist-Revised, Multi-Health System, Toronto, 1991], 33 correlated to global personality disorder (GPD) and 23 to partial personality disorder (PPD), respectively, subtypes of antisocial personality disorder [Manual for the Hare Psychopathy Checklist-Revised, Multi-Health System, Toronto, 1991]. Subjects were evaluated through psychiatric and neurological examinations, review of judicial records, Rorschach and PCL-R. A control group of 30 subjects without criminological or psychiatric history was also evaluated with the same instruments. PCL-R validation and identification of cutoff score for Psychopathy (GPD group) was assessed through the concurrent use of the Rorschach. PCL-R cutoff score for the Brazilian population was set at 23. Sensitivity was determined at 84.8%, and reliability was high (Kappa index = 0.87). GPD individuals were characterized as clearly psychopathic according to PCL-R criteria while PPD individuals can only be considered mildly psychopathic, with better chance of rehabilitation.