1. Centers for Disease Control and Prevention, Division of Nutrition and Physical Activity, Atlanta, Georgia
2. Center for Health Promotion and Disease Prevention, Schools of Public Health and Medicine, University of North Carolina, ChapelHill, North Carolina
3. UNC Clinical Center for the Study of Development andLearning, Schools of Public Health and Medicine, University of North Carolina, ChapelHill, North Carolina
4. Department of Nutrition, Schools of Public Health and Medicine, University of North Carolina, ChapelHill, North Carolina