Homework Completion, Patient Characteristics, and Symptom Change in Cognitive Processing Therapy for PTSD

Area of Science:

• Psychiatry
• Clinical Psychology
• Trauma Studies

Background:

• Posttraumatic stress disorder (PTSD) is a debilitating condition often treated with Cognitive Processing Therapy (CPT).
• Homework completion is a key component of CPT, but its specific impact on symptom change requires further investigation.
• Understanding factors influencing treatment outcomes is crucial for optimizing PTSD interventions.

Purpose of the Study:

• To evaluate the impact of homework completion frequency on changes in PTSD symptoms during CPT.
• To explore whether the version of CPT (with or without written trauma account) influences the homework-outcome relationship.
• To identify potential moderators, such as pretreatment symptom severity and education level, in the association between homework and PTSD symptom change.

Main Methods:

• Two randomized controlled trials of CPT involving 140 female participants diagnosed with PTSD were analyzed.
• Piecewise growth models were employed to examine the relationship between homework completion frequency and PTSD symptom trajectories.
• PTSD symptoms were assessed bi-sessionally, while homework completion was measured at the start of each session.

Main Results:

• Higher homework completion after sessions 2 and 3 was associated with larger overall PTSD symptom reduction and greater symptom change in those with less education.
• Increased homework completion after sessions 8 and 9 predicted greater subsequent decreases in PTSD symptoms.
• Homework engagement in the latter half of treatment was linked to reduced dropout rates.
• Initial PTSD symptom severity predicted homework completion for the first session only.

Conclusions:

• Efforts to enhance patient engagement in CPT homework may be a valuable strategy for facilitating PTSD symptom reduction.
• Homework completion appears to be a significant factor in treatment success, particularly in the later stages of therapy.
• The findings underscore the importance of homework adherence for improving outcomes and reducing dropout in CPT for PTSD.