[1] Harvard Med Sch, Dept Populat Med, 401 Pk Dr,Ste 401, Boston, MA 02215 USA
[2] Harvard Pilgrim Hlth Care Inst, 401 Pk Dr,Ste 401, Boston, MA 02215 USA
[3] Brigham & Womens Hosp, Dept Med, 75 Francis St, Boston, MA 02115 USA
[4] Ctr Dis Control & Prevent, Div Healthcare Qual Promot, Atlanta, GA USA
[5] Emory Univ, Sch Med, Dept Med, Div Hosp Med, Atlanta, GA USA
[6] Emory Univ, Sch Med, Dept Med, Div Pulm Allergy Crit Care & Sleep Med, Atlanta, GA USA
[7] Emory Crit Care Ctr, Atlanta, GA USA
[8] Univ Pittsburgh, Sch Med, Dept Crit Care Med, Clin Res Invest & Syst Modeling Acute Illness CRI, Pittsburgh, PA USA
[9] Univ Michigan, Dept Internal Med, Ann Arbor, MI 48109 USA
[10] VA Ann Arbor Hlth Syst, VA Ctr Clin Management Res, Ann Arbor, MI USA
[11] NIH, Dept Crit Care Med, Ctr Clin, Bethesda, MD 20892 USA
[12] Hosp Corp Amer, Nashville, TN USA
[13] Texas A&M Hlth Sci Ctr, Coll Med, Houston, TX USA
[14] Washington Univ, Sch Med, Dept Med, St Louis, MO 63110 USA
[15] Inst Hlth Metr, Burlington, MA USA