Standardization of Hare Psychopathy Checklist (2nd ed. –R) Among Prison and Non-Prison Population in Kaduna State-Nigeria

Ibrahim Ignatius Felix Ruwan, Ph.D., Department of Psychology, Nigerian Defence Academy, Kaduna; & Andrew E. Zamani, Ph.D., Department of Psychology, Nasarawa State University, Keffi.

The study examined the reliability, standardization, and factor structure of the Hare psychopathy checklist (PCL-R) 2^nd edition in prison and non-prison populations and the validity of the construct of SCL-90 amongst the non-prison population in Nigeria. A survey design was used to obtain data on the participants from the communities and correctional settings. Some 384 participants were used for the study, 296 (77.1%) were male, and 88(22.9%) were females. Their age ranged from 18-55 years, with a mean age of 33.03 years and a standard deviation of 9.2 years. Participants were selected through cluster and simple random sampling techniques. Data was analysed using Cronbach’s alpha, descriptive statistics of mean, standard deviation, error of mean scores, factor analysis, frequency, simple percentage estimates, and independent t-test. The results on reliability statistics of the PCL-R 2^nd edition had a Cronbach’s alpha of 0.823 and were considered highly significant. The norms for prison-population (Mean PCL-R score gender) for male was 50.52 (SD 9.9: n=177) and females 43.86 (SD 8.7: n=15); while for non-prison population (Mean PCL-R score gender) for male 48.73 (SD 9.8: n= 119) and female 52.05 (SD 9.9: n=73). Findings therefore revealed that male participants of ages 18-35 years indicated more symptoms of psychopathy. The PLC-R 2^nd edition total scores positively correlated with obsessive compulsive disorder, Interpersonal sensitivity and somatisation subscales of the SCL-90 and therefore measured what it was supposed to measure. The analysis of factor structure replicated two-factor solutions of previous studies. The result confirmed that participants manifested interpersonal, affective, lifestyle and antisocial symptoms. The results confirmed the psychometric properties of the PCL-R 2^nd edition as a measure of psychopathy in Nigeria. Therefore, it is recommended that the PCL-R be adopted as a psychological assessment tool for criminality and psychopathy by psychologists and other forensic experts who work in the Nigerian Criminal Justice System.

Key Words: Hare, Prison, Non-Prison, PCL-R, Psychopathy, Standardization