He is an applied microeconomist whose research examines the effects of government policies and social phenomena with a focus on health and biopharmaceutical sectors. His recent work has focused on the private sector effects of the Affordable Care Act, including the labor supply effects of large insurance expansions, the changes in uncompensated hospital care resulting from public insurance expansions, and the responses of nonprofit hospitals to financial shocks. His research has appeared in numerous economic and health policy journals. Garthwaite received a B.A. and a master’s degree in public policy from the University of Michigan and his Ph.D. in economics from the University of Maryland.