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.