[1] Case Western Reserve Univ, Dept Emergency Med, Metrohlth Med Ctr, Sch Med, Cleveland, OH 44109 USA
[2] Cleveland Clin Fdn, Cleveland, OH 44195 USA
[3] Stanford Univ, Sch Med, UCSF Stanford Hlth Care, Div Emergency Med, Stanford, CA 94305 USA
[4] Massachusetts Gen Hosp, Dept Emergency Med, Boston, MA 02114 USA
[5] Harvard Univ, Brigham & Womens Hosp, Sch Med, Dept Med,Channing Lab, Boston, MA 02115 USA