[1] Vanderbilt Univ, Med Ctr, Dept Emergency Med, Nashville, TN USA
[2] Vanderbilt Univ, Med Ctr, Dept Anesthesiol, Nashville, TN USA
[3] Vanderbilt Univ, Sch Med, Dept Biostat, Nashville, TN USA
[4] Vanderbilt Univ, Med Ctr, Dept Qual Safety & Risk Prevent, Nashville, TN USA
[5] PeaceHlth Sacred Heart Med, Ctr Univ Dist, Dept Emergency Med, Eugene, OR USA