Major depressive disorder (MDD) is the psychological condition most commonly comorbid with posttraumatic stress disorder (PTSD). PTSD and MDD comorbidity is associated with greater symptom severity, lower levels of functioning, greater disability, and increased suicide potential relative to PTSD or MDD alone. Unfortunately, no psychological treatment intervention specifically addresses this comorbidity. Individuals with comorbid PTSD and MDD often receive evidence-based treatments for PTSD, such as cognitive processing therapy (CPT); although such treatments typically reduce both PTSD and depression symptoms, few studies have specifically examined these outcomes in individuals with PTSD and comorbid MDD. The primary goal of this randomized controlled trial is to evaluate whether greater improvement in depression symptoms can be achieved by augmenting CPT with behavioral activation (BA), a standard depression treatment, for active-duty service members with PTSD and comorbid MDD. Participants will be evaluated at three assessment time-points (pre-treatment, post-treatment, and three-month follow-up), as well as complete self-report measures of PTSD and MDD symptoms at each therapy session.
