[1] Univ Ottawa, Dept Pediat & Emergency Med, Ottawa, ON, Canada
[2] Univ Louisville, Dept Pediat, Louisville, KY 40292 USA
[3] Brown Univ, Div Pediat Emergency Med, Alpert Med Sch, Providence, RI 02912 USA
[4] Univ Colorado, Sch Med, Denver Hlth Med Ctr, Dept Emergency Med, Aurora, CO USA
[5] Univ Calif San Diego, Dept Pediat, San Diego, CA 92103 USA
[6] New York Univ Winthrop, Dept Emergency Med, Mineola, NY USA
[7] St Christophers Hosp Children, Philadelphia, PA 19133 USA
[8] Childrens Hosp New Jersey, Newark Beth Israel Med Ctr, Dept Emergency Med, Newark, NJ USA
[9] Northwestern Univ, Dept Pediat, Feinberg Sch Med, Chicago, IL 60611 USA
[10] Columbia Univ Vagelos Coll Phys & Surg, Dept Emergency Med, New York, NY USA