1. Duke Center for Childhood Obesity Research, Duke University Medical Center, Durham, NC, USA.
2. Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA.
3. Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA.
4. Duke Office of Clinical Research, Duke University, Durham, NC, USA.
5. Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA.
6. Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, NC, USA.
7. Department of Health Behavior and Policy, Virginia Commonwealth University School of Medicine, Richmond, VA, USA.