Do DSM-5 changes to PTSD symptom cluster criteria alter the frequency of probable PTSD when screening treatment-seeking Canadian Forces members and Veterans?

Abstract: Introduction: DSM-5 diagnostic criteria revisions for post-traumatic stress disorder (PTSD) have raised concerns about PTSD prevalence – particularly the new requirement of one avoidance symptom. We examined the frequency of positive screening results for probable PTSD in treatment-seeking Canadian Armed Forces (CAF) personnel and Veterans when both DSM-5 and DSM-IV-TR symptom cluster criteria were applied. Methods: Previously collected data from 382 CAF personnel and Veterans were used to identify the frequency of positive screens using both sets of diagnostic criteria. Results: 71.2% (n=272) of participants screened positively for probable PTSD using DSM-5 symptom cluster criteria, compared to 77.7% (n=297) using DSM-IV-TR symptom cluster criteria. Percent agreement analyses found that negative percent agreement was 100.0%, positive percent agreement was 91.6%, and overall percent agreement was 93.5%. Discussion: The number of individuals who screened positively for probable PTSD using DSM-IV-TR criteria was higher than those who screened positively using DSM-5 criteria. The requirement of at least one avoidance symptom appears to have a noticeable impact on the frequency of positive screens for probable PTSD among treatment-seeking military personnel. This has important implications for pension adjudication and treatment entitlement.