Behaviour Research and Therapy, 141, Article 103846.
Cognitive Processing Therapy (CPT) is an evidence-based therapy recommended for posttraumatic stress disorder (PTSD). However, rates of improvement and remission are lower in veterans and active duty military compared to civilians. Although CPT was developed as a 12-session therapy, varying the number of sessions based on patient response has improved outcomes in a civilian study. This paper describes outcomes of a clinical trial of variable-length CPT among an active duty sample. Aims were to determine if service members would benefit from varying the dose of treatment and identify predictors of treatment length needed to reach good end-state (PTSD Checklist-5 = 19). This was a within-subjects trial in which all participants received CPT (N = 127). Predictor variables included demographic, symptom, and trauma-related variables; internalizing/externalizing personality traits; and readiness for change. Varying treatment length resulted in more patients achieving good end-state. Best predictors of nonresponse or needing longer treatment were pretreatment depression and PTSD severity, internalizing temperament, being in precontemplation stage of readiness for change, and African American race. Controlling for differences in demographics and initial PTSD symptom severity, the outcomes using a variable-length CPT protocol were superior to the outcomes of a prior study using a fixed, 12-session CPT protocol.