[1] Vanderbilt Univ, Dept Emergency Med, Med Ctr, Nashville, TN 37232 USA
[2] Vanderbilt Univ, Dept Biomed Informat, Nashville, TN 37232 USA
[3] VA Tennessee Valley Healthcare Syst, Nashville, TN USA
[4] Iowa City VA Healthcare Syst, Vet Rural Hlth Resource Ctr Iowa City, VA Off Rural Hlth, Iowa City, IA USA
[5] Iowa City VA Healthcare Syst, Ctr Access & Delivery Res & Evaluat CADRE, Iowa City, IA USA
[6] Univ Iowa, Dept Internal Med, Carver Coll Med, Iowa City, IA USA
[7] Univ Iowa, Dept Emergency Med, Carver Coll Med, Iowa City, IA USA
[8] Univ Iowa, Dept Anesthesia, Carver Coll Med, Iowa City, IA USA