[1] Harbor UCLA Med Ctr, Dept Emergency Med, Torrance, CA 90509 USA
[2] Univ Calif Los Angeles, Anderson Sch Management, Los Angeles, CA USA
[3] Univ Calif Los Angeles, David Geffen Sch Med, Dept Pediat, Los Angeles, CA 90095 USA
[4] USC, Keck Sch Med, Dept Emergency Med, Los Angeles, CA USA
[5] St Lukes Roosevelt Hosp, Dept Emergency Med, New York, NY 10025 USA
[6] Univ Calif Los Angeles, Div Dermatol, Dept Med, David Geffen Sch Med, Los Angeles, CA 90024 USA