1. Statistics and Epidemiology Unit, RTI International, Research Triangle Park, North Carolina
2. National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
3. Department of Clinical Biochemistry and Immunology, Section of Neonatal Screening and Hormones, Statens Serum Institut, Copenhagen, Denmark
4. Department of Pediatrics, Neonatal-Perinatal Medicine, Wayne State University, Detroit, Michigan
5. Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
6. Division of Neonatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama
7. Division of Perinatal Medicine, Department of Pediatrics, Yale-New Haven Children's Hospital and the Yale University School of Medicine, New Haven, Connecticut
8. Department of Pediatrics, Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio