Psychopathy and the PCL-R (Psychopathy Checklist-Revised).
Much interesting research has been conducted over the last few years on cross-cultural aspects of criminal psychopathy as defined by the PCL-R (Cooke, 1996a, 1996b, 1997, 1998a, 1998b; Cooke & Michie, 1999).
The SRP-ll is a less established measure and was developed to assess both Factor 1 and Factor 2 of the Psychopathy Checklist (PCL-R).
In an attempt to also replicate Gustafson and Ritzer's second study reported in the same article as the first one (1995), we are presently working on a project aiming to validate the ASP pattern in our sample by double-blind PCL-R interviews of a group of ASPs and a group of non-ASPs.
TABLE 2 Reliability of total scores and PCL-R factors (figures from PCL-R manual in parentheses)
Total score Factor 1 Factor 2 Alpha 0.82 (0.87) 0.77 (0.84) 0.78 (0.77) Inter-item r 0.19 (0.26) 0.29 (0.38) 0.30 (0.27) Evidence gathered over ten years demonstrates the sound reliability of the PCL-R as summarized in the PCL-R manual (Hare 1991).
Most of the data available regarding the PCL and PCL-R are derived from research conducted with North American prison populations.
Overall, this research suggests that the PCL-R is a valid and reliable method to assess psychopathy and it was, therefore, chosen for the purpose of the present study.
The aims of the present study are twofold: first, in the light of research questioning the efficacy of TCs for psychopaths, to investigate the prevalence of psychopathy in the Grendon population; and secondly, as most research involving the PCL-R has involved North American populations, to investigate the psychometric properties of the PCL-R using a UK prison population.
The Hare PCL-R was administered to 104 inmate receptions to the prison during 1995, comprising 73 per cent of receptions during this period.
As the administration of the PCL-R was an additional procedure, inmates were asked to participate on a voluntary basis.
Inter-rater reliability was established between the authors by administering the PCL-R to 11 randomly selected inmates from the assessment unit.