Psychometric properties of the PTSD Checklist for DSM-5 in a sample of trauma exposed mental health service users

Background: PTSD self-report measures are frequently used in mental health services but very few have been evaluated in clinical samples that include civilians. The PCL-5 was developed to assess for DSM-5 PTSD. Objective: The aim of this study was to evaluate the psychometric properties of the PCL-5 in a sample of trauma-exposed mental health service users who were evidencing symptoms of PTSD. Method: Reliability and validity of the PCL-5 were investigated in a sample of 273 participants who reported past diagnosis for PTSD or who had screened positively for traumatic stress symptoms. Diagnostic utility was evaluated in comparison to the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5). Results: The PCL-5 demonstrated high internal consistency, good convergent and divergent validity, acceptable stability and good diagnostic utility. However, operating characteristics differed from those found in other samples. Scores of 43–44 provided optimal efficiency for diagnosing PTSD. A post hoc regression analysis showed that depression explained more of the variance in PCL-5 total score than the CAPS-5. Conclusion: Whilst the PCL-5 is psychometrically sound it appears to have difficulty differentiating self-reported depression and anxiety symptoms from PTSD in trauma-exposed mental health service users and clinicians should take care to assess full symptomatology when individuals screen positively on the PCL-5. Clinicians and researchers should also take care not to assume that operating characteristics of self-report PTSD measures are valid for mental health service users, when these have been established in other populations.