Moderators of PTSD symptom change in group cognitive behavioral therapy and group present centered therapy.

To examine moderators of change during group-based intervention for Posttraumatic Stress Disorder (PTSD), multilevel models were used to assess trajectories of symptom clusters in male veterans receiving trauma focused Group Cognitive Behavioral Treatment (gCBT; N = 84) or non-trauma focused Group Present Centered Therapy (gPCT; N = 91; Sloan et al., 2018). Separate models were conducted for symptom clusters in each intervention, examining pre-treatment PTSD symptoms, pre-treatment depression severity, age, index trauma, and outcome expectancies as potential moderators. Unconditioned growth models for both gCBT and gPCT showed reductions in intrusions, avoidance, negative cognitions/mood, and arousal/reactivity (all p < .001). Distinct moderators of recovery emerged for each treatment. Reductions in avoidance during gCBT were strongest at high levels of pre-treatment PTSD symptoms (low PTSD: p = .964, d = .05; high PTSD: p < .001, d = 1.31) whereas positive outcome expectancies enhanced reductions in cognitions/mood (low Expectancy: p = .120, d = .50; high Expectancy: p < .001, d = 1.13). For gPCT, high levels of pre-treatment depression symptoms negatively impacted change in both intrusion (low depression: p < .001, d = .96; high depression: p = .376, d = .22) and arousal/reactivity (low depression: p < .001, d = .95; high depression: p = .092, d = .39) symptoms. Results support the importance of examining trajectories of change and their moderators for specific treatments, particularly when contrasting trauma focused and non-trauma focused treatments.

Randomized trial of trauma-focused group therapy for posttraumatic stress disorder: results from a department of veterans affairs cooperative study.

BACKGROUND: Department of Veterans Affairs Cooperative Study 420 is a randomized clinical trial of 2 methods of group psychotherapy for treating posttraumatic stress disorder (PTSD) in male Vietnam veterans. METHODS: Vietnam veterans (360 men) were randomly assigned to receive trauma-focused group psychotherapy or a present-centered comparison treatment that avoided trauma focus. Treatment was provided weekly to groups of 6 members for 30 weeks, followed by 5 monthly booster sessions. Severity of PTSD was the primary outcome. Additional measures were other psychiatric symptoms, functional status, quality of life, physical health, and service utilization. Follow-up assessments were conducted at the end of treatment (7 months) and at the end of the booster sessions (12 months); 325 individuals participated in 1 or both assessments. Additional follow-up for PTSD severity was performed in a subset of participants at 18 and 24 months. RESULTS: Although posttreatment assessments of PTSD severity and other measures were significantly improved from baseline, intention-to-treat analyses found no overall differences between therapy groups on any outcome. Analyses of data from participants who received an adequate dose of treatment suggested that trauma-focused group therapy reduced avoidance and numbing and, possibly, PTSD symptoms. Dropout from treatment was higher in trauma-focused group treatment. Average improvement was modest in both treatments, although approximately 40% of participants showed clinically significant change. CONCLUSIONS: This study did not find a treatment effect for trauma-focused group therapy. The difference between the effectiveness and adequate dose findings suggests the possible value of methods to enhance the delivery of cognitive-behavioral treatments in clinical practice settings.