[1] Childrens Hosp Philadelphia, Div Emergency Med, Philadelphia, PA 19104 USA
[2] Univ Penn, Perelman Sch Med, Dept Pediat, Philadelphia, PA 19104 USA
[3] Hosp Univ Penn, 3400 Spruce St, Philadelphia, PA 19104 USA
[4] Univ Penn, Perelman Sch Med, Dept Emergency Med, Philadelphia, PA 19104 USA
[5] Hosp Univ Penn, Emergency Med Residency, 3400 Spruce St, Philadelphia, PA 19104 USA
[6] Boston Combined Residency Program Pediat, Boston, MA USA