[1] Univ Calif San Francisco, Dept Emergency Med, San Francisco, CA 94143 USA
[2] Univ Kentucky, Dept Emergency Med, Lexington, KY USA
[3] New York Presbyterian Brooklyn Methodist Hosp, Dept Emergency Med, Brooklyn, NY USA
[4] Reg Hosp, Dept Emergency Med, St Paul, MN USA
[5] Maimonides Hosp, Dept Emergency Med, Brooklyn, NY 11219 USA
[6] Univ Chicago, Dept Med, Div Emergency Med, 5841 S Maryland Ave, Chicago, IL 60637 USA