Group-Based Acceptance and Commitment Therapy for PTSD in a HMO Psychiatry Clinic: An Open Trial

Mindfulness and acceptance-based approaches have shown promise as alternative interventions to trauma-focused therapies for PTSD. This open trial examined the potential effectiveness of an 8-session Acceptance and Commitment Therapy (ACT) group in reducing psychiatric symptoms and improving quality of life in outpatient adults (N = 86, 79% female) receiving treatment for PTSD in a health maintenance organization (HMO) psychiatry clinic. The group therapy was an adjunct to usual care and utilized the six core processes of ACT: acceptance, cognitive defusion, mindfulness, self-as-context, values, and committed action. Participants completed self-report measures of PTSD symptoms, depression, anxiety and quality of life; and self-report ACT-specific process measures of acceptance, cognitive defusion and mindfulness at pretreatment, posttreatment and 3-month follow-up. Repeated measures analyses of variance conducted with a completer sample (n = 55) demonstrated significant improvements on all variables with medium to large effect sizes at posttreatment and follow-up. The study findings support further investigation in a randomized controlled trial.