1. Department of Epidemiology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
2. Department of Nutrition, Gillings School of Global Public Health, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
3. Department of Biostatistics, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
4. Division of General Pediatrics and Adolescent Medicine, Department of Pediatrics, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
5. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC