PROJECT SUMMARY Structural racism is embedded in societal structures that limit opportunities and resources for racialized groups. This manifest as social determinants of health (SDOH)—the social circumstances in which people are born, live, and age—and as racial/ethnic health disparities. Professional medical organizations and insurers recommend screening for—and addressing—adverse SDOH within healthcare delivery. As a result, healthcare systems especially those serving low-income patients are implementing SDOH screening. Despite this rapid uptake, critical knowledge gaps remain regarding the equitable implementation and effectiveness of SDOH screening/referral systems on improving disease outcomes. Our team’s work on the WE CARE SDOH system, which leverages extant clinical staff and workflows to address families’ social needs, has demonstrated its effectiveness on increasing referrals to social services and receipt of resources among low-income families; WE CARE has been cited as an evidence-based SDOH intervention by the American Academy of Pediatrics. However, our recently completed hybrid effectiveness-implementation RCT found significantly more caregivers of color (compared to white caregivers) experiencing higher rates of double loss whereby their unmet needs were not addressed despite being disclosed. These results are likely due to suboptimal implementation related to multiple levels of discrimination that caregivers of color face in the healthcare and social service systems. With an interdisciplinary team of SDOH, implementation, antiracism, and practice-based researchers, we will apply an antiracism lens to WE CARE and develop an implementation toolkit aimed at mitigating unequal treatment for patients of color. We will conduct a hybrid effectiveness-implementation study with a stepped wedge cluster RCT design in four large family medicine (FM) clinics that serve racially/ethnically diverse low-income families from Worcester, Massachusetts. Our specific aims are to: (1) Refine the WE CARE implementation protocol using an antiracism lens and community engagement approach to: (a) conduct key informant interviews with families to identify racism-related barriers to SDOH screening/referral; (b) present these barriers to systems-level stakeholders to elicit input on strategies to address patient concerns; and create an antiracist-informed toolkit for the implementation of SDOH screening/referral systems; (2) Implement WE CARE by deploying the refined protocol in FM practices and assess implementation outcomes including equity, appropriateness, and patient-centeredness; (3) Evaluate the effectiveness of WE CARE on prevalent pediatric and adult chronic diseases outcomes. This proposal has the potential to create novel community- and patient-engaged strategies for implementing SDOH screening and referral systems into healthcare and social service systems with the potential to reduce racial/ethnic health inequities. It is aligned with the NIMHD...