Detailed item analyses of the Postraumatic Stress Disorder Checklist for DSM-5 (PCL-5): Use in public safety personnel

Abstract

Public safety personnel (PSP; e.g., correctional workers, firefighters, paramedics, police officers) are regularly exposed to diverse potentially psychologically traumatic events (PPTE). More frequent exposure to PPTE is associated with greater reporting of posttraumatic stress disorder (PTSD) symptoms. In a landmark study of Canadian PSP, more than 23% screen positively for PTSD. PSP depend on PTSD screening tools to comprehensively assess their symptoms as part of early warning systems that facilitate rapid access to evidence-based care. The PTSD Checklist – Version 5 (PCL-5) is a commonly used PTSD screening tool. A recent study (Shields et al., 2017) using the PCL-5 evidenced approximately 30% of paramedics would have screened positively for PTSD based on their self-reported symptoms, but did not because none reported avoidance symptoms. The researchers suggested avoidance might be impossible because of paramedic vocational requirements (e.g., required to return to a PPTE scene). The sample was relatively small, included only paramedics, and detailed psychometric analyses on the PCL-5 data were not conducted. The current study was designed to further assess the psychometric properties of the PCL-5 as a screening tool for PTSD among PSP. Detailed item analyses on the PCL-5 were conducted with data from large samples of PSP (n = 5813) and the Canadian general population (n = 2631). PCL-5 items were assessed for differential item functioning between PSP and the general population. Positive screening proportions were also examined for differences based on removing each symptom cluster requirement. Results indicated no statistically significant differences between PSP and the general population based on PCL-5 item analyses or functioning. In contrast, results indicated removing the avoidance criterion statistically significantly increased the proportion of positive screens among the PSP sample, but not among the general population sample. The results suggest that there are differences between PSP and the general population related to avoidance that require further investigation. The current results will be used to inform a subsequent qualitative investigation of avoidance behaviour among PSP.