1. Birth Defects Monitoring Program, State Center for Health Statistics Division of Public Health, North Carolina Department of Health and Human Services Raleigh North Carolina USA
2. Department of Epidemiology, Gillings School of Global Public Health University of North Carolina at Chapel Hill Chapel Hill North Carolina USA
3. Division of Pediatric Cardiology, Children's Healthcare of Atlanta; and School of Medicine Emory University Atlanta Georgia USA
4. Division of Birth Defects and Infant Disorders National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention Atlanta Georgia USA
5. Birth Defects Registry New York State Department of Health Albany New York USA
6. Birth Defects Epidemiology and Surveillance Branch Texas Department of State Health Services Austin Texas USA
7. Department of Epidemiology, College of Public Health University of Iowa Iowa City Iowa USA
8. Massachussets Center for Birth Defects Research and Prevention Massachusetts Department of Public Health Boston Massachusetts USA
9. Department of Epidemiology, College of Public Health; and Department of Pediatrics, College of Medicine University of Arkansas for Medical Sciences Little Rock Arkansas USA
10. Department of Pediatrics Stanford University School of Medicine Stanford California USA