1. Department of Epidemiology Emory University Rollins School of Public Health Atlanta Georgia
2. National Center for HIV/AIDS Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention Atlanta Georgia
3. National Center for Chronic Disease Prevention and Health Promotion Centers for Disease Control and Prevention Atlanta Georgia
4. Division of Nuclear Medicine and Molecular Imaging Department of Radiology Emory University Hospital Atlanta Georgia
5. Center for Spina Bifida Research Prevention and Policy, Emory University, Rollins School of Public Health Atlanta Georgia