[1] Rush Univ, Med Ctr, Dept Emergency Med, 1750 West Harrison St,Suite 108 Kellogg, Chicago, IL 60612 USA
[2] Duke Univ, Dept Emergency Med, Durham, NC USA
[3] Univ Michigan, Dept Emergency Med, Ann Arbor, MI USA
[4] Milton S Hershey Med Ctr, Penn State Hlth, Dept Emergency Med, Hershey, PA USA
[5] USC, Keck Sch Med, Dept Med, Los Angeles, CA USA
[6] USC, Keck Sch Med, Dept Emergency Med, Los Angeles, CA USA