1. US Public Health Service, Rockville, Maryland2Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland
2. Division for Heart Disease and Stroke Prevention, National Center for Chronic Disease Prevention and Health Promotion, Atlanta, Georgia
3. Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland
4. Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Atlanta, Georgia