Was it helpful? Treatment outcomes and practice assignment adherence and helpfulness among U.S. service members with PTSD and MDD

Practice assignments (i.e. homework) are a key component in cognitive behavioral therapies that predict treatment outcomes for posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) separately. However, research has not explored these variables among individuals with comorbid PTSD and MDD. This study evaluated whether practice assignment adherence and helpfulness predicted PTSD (Clinician-Administered PTSD Scale for DSM-5; CAPS-5) and MDD (Montgomery-Åsberg Depression Rating Scale; MADRS) outcomes at posttreatment and 3-month follow-up. Data were derived from a randomized clinical trial comparing cognitive processing therapy (CPT) and behavioral activation-enhanced CPT (BA+CPT) among 83 U.S. active duty service members with comorbid PTSD and MDD. Participants reported greater assignment adherence in BA+CPT than CPT (<i>p</i> = .008), primarily due to higher adherence to BA assignments within BA+CPT. Multilevel models indicated helpfulness ratings were significantly related to decreased CAPS-5 scores (<i>p</i> = .044) but not MADRS scores (<i>p</i> = .074); service members with the highest helpfulness ratings achieved the best outcomes. Adherence was not significantly related to CAPS-5 (<i>p</i> = .494) or MADRS (<i>p</i> = .114) outcomes. Findings provide clinical insights regarding compliance in integrated treatments and highlight the value in assessing helpfulness of practice assignments during treatment.