[1] Vanderbilt Univ, Ctr Med, Dept Biomed Informat, Eskind Biomed Lib, Nashville, TN 37232 USA
[2] Vanderbilt Univ, Dept Emergency Med, Nashville, TN USA
[3] Univ Utah, Div Med Eth, LDS Hosp, Salt Lake City, UT USA
[4] Univ Utah, Dept Med Informat, LDS Hosp, Salt Lake City, UT 84112 USA
[5] Univ Utah, Div Pulm Med, LDS Hosp, Salt Lake City, UT USA