1. Division of Emergency Medicine and Department of Pediatrics, Children's National Medical Center, George Washington University School of Medicine and Health Sciences, Washington, DC
2. Division of Pediatric Emergency Medicine, Alfred I. duPont Hospital for Children, Wilmington, Delaware
3. Division of Pediatric Emergency Medicine, Mount Sinai Hospital Center, New York, New York
4. Division of Pediatric Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, Texas