Current understanding of how and why race influences the transition from acute to chronic pain following traumatic injury remains limited. Traumatic injuries result in over 30 million emergency department visits and 2.5 million hospitalizations each year in the U.S. Risk for developing post-injury chronic pain is significantly greater for non-Hispanic Black (NHB) patients compared to non-Hispanic White (NHW) patients with similar injuries. Although NHB patients experience higher levels of acute post-injury pain and are more likely to transition to chronic pain than NHW patients, the biobehavioral and social factors that influence this transition are not well understood. The overall aim of this proposal is to improve understanding of the factors that influence the transition to post-injury chronic pain and shape racial pain disparities. To address our aims, we will recruit 150 NHB and 150 NHW adults with traumatic orthopedic injuries from a level 1 trauma center and assess pain outcomes during hospitalization and across monthly follow-ups. First, we will identity similarities and differences in the extent to which biobehavioral factors explain post-injury chronic pain in NHB and NHW patients. We hypothesize that greater pain sensitivity (assessed in hospital via quantitative sensory testing), elevated acute inflammatory biomarkers (hsCRP, TNFα, IL1β, IL-6), more negative cognitions (catastrophizing, pain/treatment expectations), and higher depressive/posttraumatic stress symptoms will predict post-injury chronic pain (i.e., higher odds of chronic pain onset, greater pain intensity and interference) in both NHB and NHW patients. If chronic pain risks are moderated by race, we hypothesize that worse post-injury chronic pain in NHB relative to NHW patients will be explained, in part, by higher biobehavioral risk factors. Second, we will identify similarities and differences in the extent to which social factors explain post-injury chronic pain in NHB and NHW patients. We hypothesize that social risk factors (greater life and neighborhood stress, lower socioeconomic status) will predict post-injury chronic pain in both NHB and NHW patients, and that social protective factors (higher social support) will buffer against in the influence of social risk factors. If chronic pain risks are moderated by race, we hypothesize that worse post-injury chronic pain in NHB relative to NHW patients will be explained, in part, by higher levels of social risk factors. The comprehensive assessment of risk and protective factors across multiple levels of the biopsychosocial model will advance understanding of the pathways that contribute to post-injury chronic pain for both NHB and NHW adults, including factors implicated in racial differences in transition to chronic pain. Evaluating in-hospital evoked pain sensitivity as a predictor of post-injury chronic pain development represents a major innovation. This knowledge could spur the development of cost-effective, scala...