1. Department of Epidemiology, Rollins School of Public Health, Emory University, and Guest Researcher, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia.
2. National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia.
3. North Carolina Birth Defects Monitoring Program, North Carolina State Center for Health Statistics, North Carolina Division of Public Health, North Carolina Department of Health and Human Services, Raleigh, North Carolina.
4. University of North Carolina, and Dental Friends Distinguished Professor, Dental Ecology, School of Dentistry, University of North Carolina Craniofacial Center, Chapel Hill, North Carolina.