1. a Duke University Center for Health Policy, Law and Management , USA
2. b Center for AIDS Research, University of North Carolina at Chapel Hill , USA
3. c Cecil G. Sheps Center for Health Services Research , USA
4. d Department of Health Behavior and Health Education , University of North Carolina School of Public Health , USA
5. e Division of General Internal Medicine and Epidemiology, Department of Medicine , University of North Carolina School of Medicine , USA
6. f Division of Pharmaceutical Policy and Evaluative Sciences , University of North Carolina at Chapel Hill School of Pharmacy , USA