Comparative Effectiveness of Prolonged Exposure and Cognitive Processing Therapy for Military Service Members in an Intensive Treatment Program

Objective: While the comparative efficacy of prolonged exposure (PE) and cognitive processing therapy (CPT) has been examined in outpatient settings, there is a dearth of literature on the relative effectiveness of these interventions when adapted for an intensive treatment format. In an expanded secondary analysis of a previous study, we sought to examine the comparative effectiveness of PE and CPT delivered in the naturalistic setting of an intensive treatment format including maintenance of outcomes through a 6-month follow-up period. Method: A sample of 296 veterans with posttraumatic stress disorder (PTSD) received either PE (n = 186) or CPT (n = 90), alongside other trauma-informed interventions, in a 2-week intensive clinical program. Treatment selection was determined collaboratively between patient and therapist. Our primary outcome was self-reported PTSD symptom severity (i.e., PTSD Checklist for DSM-5, PCL-5); secondarily, we examined self-reported depression (i.e., Patient Health Questionnaire) symptom severity outcomes. Results: A mixed-model regression controlling for age and gender revealed a significant effect of time from baseline to endpoint (p < .001), 3-month (p < .001), and 6-month follow-up (p < .001) on PCL-5 scores but no significant effect of treatment or effect of treatment by time interaction (all ps > .05; model: Wald's χ2 = 232.38, p < .001). Results were similar for depression outcomes. Attrition at posttreatment was not significantly different between groups: 7.2% for CPT and 6.5% PE (z score = 0.22). Conclusions: Both PE and CPT are associated with comparable improvements when delivered as part of a 2-week intensive outpatient program. Clinical Impact Statement Cognitive processing therapy (CPT) and prolonged exposure (PE) therapy were comparably effective when delivered daily, alongside other trauma-informed interventions, as part of a 2-week intensive outpatient program for veterans with posttraumatic stress disorder (PTSD). Both treatments were associated with low (< 10%) dropout rates and similarly maintained gains up to 6 months following treatment. Both CPT and PE can be effectively adapted to an eight-session format and delivered daily as part of an intensive treatment program with large reductions in self-reported PTSD and depression symptoms.