Predictors of Initiation and Engagement of Cognitive Processing Therapy Among Veterans With PTSD Enrolled in Collaborative Care.

Collaborative care (CC) increases access to evidence-based pharmacotherapy and psychotherapy. The study aim was to identify the characteristics of rural veterans receiving a telemedicine-based CC intervention for posttraumatic stress disorder (PTSD) who initiated and engaged in cognitive processing therapy (CPT) delivered via interactive video. Veterans diagnosed with PTSD were recruited from 11 community-based outpatient clinics (N = 133). Chart abstraction identified all mental health encounters received during the 12-month study. General linear mixed models were used to identify characteristics that predicted CPT initiation and engagement (attendance at 8 or more sessions). For initiation, higher PTSD severity according to the Clinician Administered PTSD Scale (d = -0.39, p = .038) and opt-out recruitment (vs. self-referral; d = -0.49, p = .010) were negative predictors. For engagement, major depression (d = -1.32, p = .006) was a negative predictor whereas a pending claim for military service connected disability (d = 2.02, p = .008) was a positive predictor. In general, veterans enrolled in CC initiated and engaged in CPT at higher rates than usual care. Those with more severe symptoms and comorbidity, however, were at risk of not starting or completing CPT.