1 Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Mass. Electronic address: [email protected].
2 Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Mass.
3 Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Mass; Department of Health Science, University of Yamanashi, Chuo, Yamanashi, Japan.
4 Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, Mass.
5 Division of Emergency Medicine, Children's National Hospital, Washington, DC.