Online Yoga vs Acceptance and Commitment Therapy for Treating Chronic Musculoskeletal Pain - PROJECT SUMMARY/ABSTRACT More than 50% of veterans in primary care report experiencing chronic pain. Chronic pain is treatment- resistant, and medications often include the risk of addiction or overdose. In recognition of the scope of this problem, the VA has encouraged the use of complementary and integrative health (CIH) in conjunction with conventional pain treatments. Yoga is a popular CIH approach and is effective in treating many types of chronic pain, including musculoskeletal pain which is the most common type. While all yoga is potentially therapeutic, online delivery of yoga (“teleyoga”) has many advantages over in-person yoga; it can reach individuals who lack access to healthcare due to geography, poor health, or other barriers. The use of telehealth has become widespread, and the high utilization of yoga for treating chronic pain illustrates a need for high quality evidence for the efficacy of teleyoga. However, no randomized clinical trial (RCT) has asked whether teleyoga is an effective treatment for chronic musculoskeletal pain. To address this research gap, we recently completed an NCCIH-funded R34 feasibility study of teleyoga for treating chronic musculoskeletal pain in veterans. We showed that a synchronous teleyoga protocol delivered in real-time over Zoom to groups of veterans was a feasible treatment and that it had promise for alleviating pain. We now propose a fully powered RCT to evaluate the efficacy of teleyoga for chronic musculoskeletal pain. We argue the most impactful design is to compare teleyoga to a standard pain treatment. We will use Acceptance and Commitment Therapy (ACT) as a comparison group as it is the most robust nonpharmacological treatment available for musculoskeletal pain, it is recommended by the VA and American Psychological Association and has demonstrated efficacy in veteran populations. A noninferiority design will be used as appropriate for trials in which the primary objective is to show a novel intervention (teleyoga) is clinically noninferior to a standard well-established treatment (ACT). We will recruit and randomize 328 veterans with chronic musculoskeletal pain to one of two groups (teleyoga, ACT; n=164 per group) and treatment will be delivered to groups of approximately 5 individuals online over 8-weeks (ACT) or 12-weeks (teleyoga). Measures will be taken at baseline, end-of-treatment, and 6 months after treatment, and will include pain interference with daily activities (primary outcome), pain severity, depression, sleep, and dropout. We expect pain interference will improve in both groups following treatment, and that teleyoga will not be clinically inferior to ACT. Overall, this trial seeks to provide high-quality evidence for the efficacy of teleyoga as a treatment for chronic musculoskeletal pain. The results will help promote teleyoga as a scalable, accessible, and effective treatment.