Addressing COVID-19 Testing Disparities in Vulnerable Populations Using a Community JITAI (Just in Time Adaptive Intervention) Approach: RADx-UP Phase III

Background: The purpose of this study was to reduce COVID-19 morbidity, mortality, and inequities among underserved populations in Texas. Vulnerable groups with medical comorbidities, people living in rural settings, and racial and ethnic minorities experienced significant disparities, with Hispanics and Blacks far more likely to be infected and hospitalized than White non-Hispanics. The study built on previous studies to increase SARS-CoV-2 testing, vaccination, and risk-mitigation behaviors in three racially diverse regions: Houston and Harris County, South Texas, and Northeast Texas. The study leveraged partnerships and resources of the Center for Clinical and Translational Science, including long-standing community partnerships, to reach these communities effectively.

Materials/Methods: This study used mixed methods and community-engaged approaches to adapt or create multilevel intervention messages, materials, and strategies aimed at increasing rapid SARS-CoV-2 testing, addressing social determinants of health, and countering misinformation. Aim 1 expanded surveillance data to track infection, testing, and vaccination trends and guide intervention decisions. Aim 2 adapted and implemented a multilevel community just-in-time adaptive intervention (MC-JITAI) informed by prior data, misinformation monitoring, and social network information. Aim 3 evaluated the adapted MC-JITAI and assessed how social network-based enhancements improved testing and vaccination across the three Texas regions.

Outcome/Impact: The intended outcomes for the study were to increase SARS-CoV-2 testing, vaccination, and mitigation behaviors among underserved and vulnerable populations in Texas, and address misinformation and social determinants of health to help reduce disparities in COVID-19 outcomes. The evaluation in Aim 3 produced baseline measures for the intervention arm and showed how the adapted strategies performed in real settings.