[1] Massachusetts Gen Hosp, Dept Emergency Med, Boston, MA 02114 USA
[2] Univ Colorado, Sch Med, Dept Emergency Med, Aurora, CO USA
[3] Weill Cornell Med, Dept Emergency Med, New York, NY USA
[4] Thomas Jefferson Univ, Dept Emergency Med, Philadelphia, PA 19107 USA
[5] Emory Univ, Dept Radiol & Imaging Sci, Atlanta, GA 30322 USA
[6] Vanderbilt Univ, Med Ctr, Dept Emergency Med, Nashville, TN USA
[7] Columbia Univ, Coll Phys & Surg, Dept Emergency Med, New York, NY USA
[8] Univ Southern Calif, Keck Sch Med, Dept Emergency Med, Los Angeles, CA 90007 USA
[9] Harbor UCLA Med Ctr, Dept Emergency Med, Torrance, CA 90509 USA