[1] Johns Hopkins Univ, Pulm & Crit Care Med, Baltimore, MD USA
[2] Johns Hopkins Univ, Baltimore, MD USA
[3] Duke Univ, Med Ctr, Div Pulm & Crit Care Med, Durham, NC USA
[4] Intermt Med Ctr, Dept Med, Murray, UT USA
[5] Univ Colorado, Colorado Sch Publ Hlth, Epidemiol, Aurora, CO USA
[6] Harbor UCLA Med Ctr, Torrance, CA 90509 USA
[7] Brigham & Womens Hosp, 75 Francis St, Boston, MA 02115 USA
[8] Natl Jewish Hlth, Denver, CO USA
[9] Los Angeles BioMed Rsch Inst, Torrance, CA USA
[10] Univ Michigan, Pulm & Crit Care Med, Ann Arbor, MI 48109 USA
[11] Los Angeles Biomed Res Inst, Torrance, CA USA
[12] Columbia Univ, Presbyterian Hosp, Med Ctr, New York, NY USA