1. Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota
2. Social, Statistical, and Environmental Sciences Unit, RTI International, Research Triangle Park, North Carolina
3. Department of Pediatrics, University of Iowa, Iowa City
4. Department of Pediatrics, University of Alabama at Birmingham
5. Department of Pediatrics, Stanford University, Palo Alto, California
6. Department of Pediatrics, Brown University, Providence, Rhode Island
7. Department of Pediatrics, University of Texas Health Science Center at Houston
8. Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas
9. Children’s Health Research Center, Sanford Research, Sioux Falls, South Dakota
10. Department of Pediatrics, University of Pennsylvania, Philadelphia
11. Social, Statistical, and Environmental Sciences Unit, RTI International, Rockville, Maryland
12. Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland