Comparing the Ratio of Therapist Support to Internet Sessions in a Blended Therapy Delivered to Trauma-Exposed Veterans: Quasi-experimental Comparison Study

BACKGROUND: Blended models of therapy, which incorporate elements of both internet and face-to-face methods, have been shown to be effective, but therapists and patients have expressed concerns that fewer face-to-face therapy sessions than self-guided internet sessions may be associated with lower therapeutic alliance, lower program completion rates, and poorer outcomes. OBJECTIVE: A multisite quasi-experimental comparison study with a noninferiority design implemented in routine clinical care was used to assess webSTAIR, a 10-module blended therapy derived from STAIR (skills training in affective and interpersonal regulation) for trauma-exposed individuals delivered with 10 weekly therapist sessions (termed Coach10) compared to 5 biweekly sessions (Coach5). It was hypothesized that Coach5 would be as good as Coach10 in a range of outcomes. METHODS: A total of 202 veterans were enrolled in the study with 101 assigned to Coach5 and 101 to Coach10. Posttraumatic stress disorder (PTSD) symptoms, depression, emotion regulation, interpersonal problems, and social functioning measures were collected pre-, mid-, and posttreatment, and at a 3-month follow-up. Noninferiority analyses were conducted on symptom outcome measures. Comparisons were made of continuous and categorical measures regarding participant and therapist activities. RESULTS: Participants reported moderate to severe levels of baseline PTSD, depression, or both. Significant reductions were obtained in all symptom measures posttreatment and at the 3-month follow up. Coach5 was not inferior to Coach10 in any outcome. Therapeutic alliance was at an equivalently high level across the 2 treatment conditions; completion rates and web usage were similar. Total session time was substantially less for the Coach5 therapists than the Coach10 therapists. Both programs were associated with a low, but equal number of therapist activities related to scheduling and crisis or motivational sessions. CONCLUSIONS: A blended model delivered with 5 sessions of therapist support was noninferior to 10 sessions in individuals with moderate to severe symptoms. Future studies identifying patient characteristics as moderators of outcomes with high versus low doses of therapist support will help create flexible, technology-based intervention programming.