The Factor Structure and Validity of the Psychopathy Checklist‐Short Version When Used With Autistic Psychiatric Inpatients

The Psychopathy Checklist Short Version (PCL:SV) is a brief measure of psychopathy. This study aimed to assess the reliability and validity of the PCL:SV with autistic adults detained in inpatient psychiatric care. Data were collected from 282 autistic adults at two time points separated by 12-months. Reliability and validity were investigated using omega, regression, receiver operating characteristic curves, and correlational analysis. PCL:SV Total, Factor 1, and Factor 2 had satisfactory to high reliability and construct validity. Higher PCL:SV scores were associated with poorer treatment progress, a longer length of stay, and previous criminal offending. Factor 1 was associated with a forensic history, detention under Part III of the Mental Health Act, and a personality disorder diagnosis, while Factor 2 was also associated with the absence of a forensic history, detention under Part II of the Mental Health Act, but not a personality disorder diagnosis. It was thought that Factor 2 most likely captured data associated with autism and/or intellectual disabilities (e.g., behaviors that challenge). Those with intellectual disabilities were less likely to have convictions, a history of violent offending, or a forensic history. They were also more likely to be detained under Part II of the Mental Health Act, and were more likely to have had a positive transfer 12-months later to a ward with lesser security. The PCL-SV correlated as expected with the HCR-20 and the START. This study provides preliminary evidence to support the use of the PCL:SV with autistic adults, including those with intellectual disabilities, within inpatient psychiatric hospitals.