1. Cecil G. Sheps Center for Health Services Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
2. Department of Nutrition at Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
3. University of North Carolina Center for Health Promotion and Disease Prevention, Chapel Hill, North Carolina, USA
4. University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
5. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
6. Larner College of Medicine at The University of Vermont, Burlington, Vermont, USA
7. Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
8. Department of Health Policy and Management at the University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
9. George Washington University School of Medicine, Washington, D.C., USA