[1] Univ Calif San Francisco, Dept Emergency Med, San Francisco, CA 94143 USA
[2] Kaiser Permanente South San Francisco Med Ctr, San Francisco, CA USA
[3] Dascena Inc, 414 13th St,Suite 500, Oakland, CA 94612 USA
[4] Univ Calif Berkeley, Dept Stat, Berkeley, CA 94720 USA
[5] Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA