Feasibility randomized controlled trial of the mobile anger reduction intervention for veterans with posttraumatic stress disorder

Dysregulated anger is a prevalent concern for veterans with posttraumatic stress disorder (PTSD) and is associated with negative psychosocial outcomes. The tendency to perceive ambiguous interpersonal situations as hostile, also known as hostile interpretation bias, is associated with problematic anger. In the present study, we report on a feasibility randomized control trial (RCT) that sought to evaluate the feasibility and acceptability of the Mobile Anger Reduction Intervention (MARI) mobile application (app), which utilizes interpretation bias modification techniques to modify hostile interpretation bias in veterans with PTSD. Veterans with PTSD and elevated anger (N = 30) were randomly assigned to use either the MARI app (n = 16) or a mindfulness app (n = 14) for 4 weeks. Participants completed self-report questionnaires assessing anger, PTSD and depressive symptoms, suicidal ideation, and functional impairment at pretreatment, posttreatment, and 3-month follow-up assessments. The primary outcomes were acceptability and feasibility. Clinical outcomes were secondary. All a priori feasibility and acceptability benchmarks for the MARI app were met or exceeded, indicating that the app is an acceptable intervention for veterans with PTSD, and additional research of the intervention is feasible. Participants in the MARI condition demonstrated large reductions in hostile interpretation bias, d = -1.12, and moderate reductions in past-week anger, d = -0.65, and trait anger, d = -0.72, from pretreatment to posttreatment. Given the demonstrated feasibility and acceptability of the MARI app, in addition to the observed clinical improvements, a larger RCT of MARI for veterans with PTSD is warranted.