1. Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill
2. Division of General Medicine & Clinical Epidemiology, University of North Carolina at Chapel Hill School of Medicine
3. Department of Health Policy, Gillings School of Global Public Health, University of North Carolina at Chapel Hill
4. Center for Drug Safety and Effectiveness, Johns Hopkins University, Baltimore, Maryland
5. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland