PROJECT ABSTRACT Each year in the U.S., over 3 million people survive critical illness only to experience long-term physical, cognitive, and psychological impairments that contribute to ongoing morbidity, mortality, and high-cost, high- utilization healthcare needs. Current fragmented, deficit-based health services delivery contributes to poor outcomes and preventable rehospitalizations. In response to this gap, we used community engagement to redesign a pragmatic, accessible, scalable, strengths-based care model that integrates 3 essential elements: (1) transitional care management; (2) problem-solving rehabilitation; and (3) family support. The result is the PIC-TRFS, which stands for Post-Intensive Care Transitional care, Rehabilitation, and Family Support. PIC-TRFS is a hybrid in-person and telehealth intervention delivered by an interdisciplinary team to nimbly support health, rehabilitation, and social care needs in collaboration with existing hospital, home health, and primary care infrastructure across transitions from hospital to home in the six months following a critical illness hospitalization. An ongoing pilot is demonstrating feasibility, acceptability, and engagement among survivors, caregivers, and providers across the post-ICU continuum. This proposal represents the next step: a single- center randomized controlled trial to establish the efficacy of PIC-TRFS. Compared to Enhanced Usual Care (n=80), we hypothesize that PIC-TRFS (n=80) will: (1) improve survivor-and caregiver outcomes including survivor quality of life (primary outcome), days alive at home, function, trauma symptoms, and caregiver quality of life (secondary outcomes); and (2) reduce healthcare utilization, measured as a composite of days in a healthcare facility, ED visits, and outpatient visits (secondary outcomes) (Aim 1). Assessing fidelity to intervention delivery, receipt, and enactment will inform potential tweaks to PIC-TRFS and resource planning for future implementation research (Aim 2). Finally, we will explore the extent to which clinical and social vulnerability moderate the impact of PIC-TRFS and dyadic activation, participation, and access to community services mediate it (Aim 3). Successful conduct of this RCT will establish the efficacy of PIC-TRFS, generate insight into mechanisms of action, identify groups for whom it requires further adaptation to promote equity, and inform its subsequent implementation. It will be a major step toward the goals of expanded access to high- quality, affordable care via scalable models of integrated service delivery. It is also a pragmatic step towards realizing the AHRQ’s broader vision for implementing learning health systems that continually innovate to optimize the delivery of safe, effective, equitable, accessible, high-quality care.