An Examination of the Relationship Between the Presence of Critical Session Elements and Treatment Outcome in Cognitive Processing Therapy for PTSD

Abstract

Cognitive Processing Therapy (CPT) is designated an evidence-based treatment, and is well supported in both the efficacy and effectiveness literature. However, while adherence to the CPT protocol is tracked during the training process, and encouraged thereafter, no literature could be found to date linking overall adherence to the protocol or specific session elements to treatment outcomes. This study sought to examine the relationship between therapist adherence to the CPT protocol and treatment outcome as measured by posttraumatic stress disorder (PTSD) and depression symptoms. The present study utilized an explanatory correlational design and employed a retrospective chart review, to gather data from CPT national progress note templates used within the Veterans Health Administration electronic health records system. Data from 55 Veterans charts from 15 states, who completed 12 sessions of CPT, and whose charts included measures of PTSD and depression symptoms were included in the study. The study utilized simultaneous multiple regressions to investigate the relationship between overall therapist adherence rates, adherence to specific elements of CPT, and treatment outcomes. Results indicated CPT was an effective treatment in this sample, reducing both PTSD and depression symptoms significantly, and demonstrated large effect sizes. Interestingly, overall therapist adherence rate did not account for a significant portion of the variance in final scores on the PTSD Checklist for DSM-5 (PCL-5) or the Patient Health Questionnaire (PHQ-9). When considering individual session elements of CPT, six were significant predictors of final scores on the PCL-5. Asking clients to complete practice assignments at the end of each session and reviewing intimacy related Challenging Belief Worksheets (CBW) in session 12 predicted decreases in PTSD symptoms as measured by the PCL-5. Conversely, addressing client concerns and questions about treatment, discussing and assigning the trauma account, introducing CBW’s, and introducing the intimacy module predicted increases in final PCL-5 scores. The following dissertation discusses the implications of these findings within the context of the current literature and contains suggestions for future research.