1. North Carolina Birth Defects Monitoring Program, State Center for Health Statistics Raleigh North Carolina
2. Department of EpidemiologyGillings School of Global Public Health, University of North Carolina at Chapel Hill Chapel Hill North Carolina
3. Department of Ophthalmology and PediatricsDuke University Medical Center Durham North Carolina
4. Department of Pediatrics and GeneticsUniversity of North Carolina at Chapel Hill Chapel Hill North Carolina
5. Department of Maternal and Child HealthGillings School of Global Public Health, University of North Carolina at Chapel Hill Chapel Hill North Carolina