His research focuses on how socioeconomic and sociocultural factors influence health behaviors and health outcomes and on mobilizing community action to address the social determinants of health. He currently leads the Healthy Equity Works (formerly For the Sake of All ), which focuses on improving the health of all people by eliminating racial inequities in the St. Louis region through the implementation of strategies related to the six areas of recommendation in the For the Sake of All report.
Purnell joined BJC Healthcare as vice present of community health improvement in 2020. This newly created role oversees the development, implementation, and evaluation of BJC’s community health program.
Purnell is trained in both applied psychology and public health. He is a faculty affiliate with the Prevention Research Center and the Center for Public Health Systems Science at the Brown School, a faculty scholar in the Institute for Public Health, and faculty director for Thriving Communities in the Center for Social Development.
Purnell is very active in the St. Louis community, including service on the boards of Beyond Housing, Inc. and the American Youth Foundation. He is also a licensed psychologist in the state of Missouri and a former director of community engagement with the United Way of Greater St. Louis.