1. Department of General Pediatrics and Adolescent Medicine, Children's National Medical Center, Washington, DC
2. Children's Research Institute, Washington, DC
3. George Washington University School of Medicine, Washington, DC
4. National Institutes of Child Health and Human Development, Department of Health and Human Services, Bethesda, Maryland
5. Department of Emergency Medicine, Children's National Medical Center, Washington, DC
6. Coleman, Sachs, and Thillairajah Pediatrics, Rockville, Maryland