1. Department of Pediatrics, Wayne State University, Detroit, Michigan;
2. Social, Statistical, and Environmental Sciences Unit, RTI International, Rockville, Maryland;
3. Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas;
4. Division of Neonatal and Developmental Medicine, Department of Pediatrics, School of Medicine, Stanford University and Lucile Packard Children’s Hospital, Palo Alto, California;
5. Department of Pediatrics, University of Rochester Medical Center, Rochester, New York;
6. Department of Pediatrics, University of Pennsylvania, Philadelphia, Pennsylvania;
7. Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama;
8. Department of Pediatrics, Duke University, Durham, North Carolina;
9. Department of Pediatrics, Women and Infants Hospital of Rhode Island, Providence, Rhode Island;
10. Department of Pediatrics, The Ohio State University and Nationwide Children’s Hospital, Columbus, Ohio;
11. Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;
12. Department of Pediatrics, University of Iowa, Iowa City, Iowa; and
13. Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland