[1] Stanford Univ, Dept Med, Div Pulm & Crit Care Med, Stanford, CA 94305 USA
[2] Stanford Univ, Sch Med, Lane Med Lib & Knowledge Management Ctr, Stanford, CA 94305 USA
[3] Stanford Univ, Dept Med, Stanford, CA 94305 USA
[4] Stanford Univ, Dept Anesthesiol, Stanford, CA 94305 USA
[5] Stanford Univ, Stanford, CA 94305 USA
[6] Amer Acad Hosp & Palliat Med, Chicago, IL USA
[7] Univ Rochester, Med Ctr, Rochester, NY 14627 USA
[8] Univ Calif San Francisco, San Francisco, CA 94143 USA
[9] St Jude Childrens Res Hosp, 332 N Lauderdale St, Memphis, TN 38105 USA
[10] Duke Canc Inst, Durham, NC USA
[11] Loyola Univ, Stritch Sch Med, 2160 S 1st Ave, Maywood, IL 60153 USA
[12] Wake Forest Sch Med, Winston Salem, NC 27101 USA
[13] Vanderbilt Univ Sch Med, Nashville, TN USA
[14] Tennessee Valley Healthcare Syst, Chattanooga, TN USA
[15] Dana Farber Canc Inst, Boston, MA 02115 USA
[16] Carolinas Healthcare, Charlotte, NC USA