1. Division of Neonatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama
2. RTI International, Research Triangle Park, North Carolina
3. Centers for Disease Control and Prevention, Atlanta, Georgia
4. Department of Obstetrics and Gynecology, Lillebaelt Hospital, Kolding, Denmark
5. Statens Serum Institut, Copenhagen, Denmark
6. NICHD Neonatal Research Network, Bethesda, Maryland