The efficacy of written exposure therapy versus imaginal exposure delivered online for posttraumatic stress disorder: Design of a randomized controlled trial in Veterans

Adapting evidence-based treatments for online delivery has potential to significantly increase the reach of effective care to Veterans with posttraumatic stress disorder (PTSD). This paper describes the rationale for and methods of a randomized controlled trial comparing the efficacy and efficiency of written exposure therapy versus imaginal exposure for PTSD delivered in a novel online and variable length format. Participants will be 300 Veterans seeking treatment for clinically significant symptoms of PTSD. Participants will be randomly assigned to either written exposure or imaginal exposure via verbal recounting and will complete between 4 and 8 online therapy sessions facilitated by trained peer support specialists. Treatment is terminated before session 8 if the PTSD symptom improvement criterion is met. Assessments will be conducted at baseline, post-treatment, and at 3-month follow-up. The primary hypotheses are that written exposure therapy will be noninferior to imaginal exposure with respect to treatment efficacy and efficiency. Secondary hypotheses relate to identifying and comparing potential mediators of PTSD treatment outcome, including trauma-related cognitions and emotion regulation.