The effects of sex and trauma type on PTSD symptom reduction in Cognitive Processing Therapy

Cognitive Processing Therapy (CPT) is an evidence-based treatment for posttraumatic stress disorder (PTSD) that is effective for many, but not all, people. The present study investigated a possible interaction of sex and trauma type to predict variable responses to treatment. Veterans from an outpatient Veterans Health Administration clinic (N = 400) completed the PTSD Checklist before CPT initiation and after treatment completion. Veterans' index traumatic events were coded by PTSD specialists as military operations-related or nonmilitary operations-related traumas. The final symptom levels were compared to the pre-assessment, determining treatment success and symptom-point reduction. Comparisons with regression models were calculated, testing sex and trauma types as predictors of PTSD symptom reduction at the end of treatment. Sex was a small but significant independent predictor of final PTSD symptom severity, such that women reported lower PTSD symptom scores than men by the end of CPT (B = -7.89, p = .001, η² = .042). Trauma type was also a significant independent predictor with a small effect on final PTSD symptoms (B = 4.04, p =.017, η² = .02) indicating that those with nonmilitary operations-related traumas reported higher final PCL-5 scores than those with military operations-related traumas. The interaction of sex and trauma type was not significant (B = 8.22, p = .097). These findings add to a growing body of literature that while male and female Veterans report significant benefit from CPT, on average, that male Veterans may not benefit as much from CPT as female Veterans. These findings also suggests that trauma type may also influence treatment outcomes. Clinical implications are presented.