[1] Harvard Med Sch, Boston Childrens Hosp, Dept Emergency Med & Pediat, Div Emergency Med, BCH 3066,300 Longwood Ave, Boston, MA 02115 USA
[2] Floating Hosp Children, Dept Emergency Med, Tufts Med Ctr, Boston, MA USA
[3] Massachusetts Gen Hosp, Emergency Med Network, Boston, MA 02114 USA
[4] Yale Univ, Sch Med, Dept Pediat, New Haven, CT 06510 USA
[5] Yale Univ, Sch Med, Dept Emergency Med, New Haven, CT USA