1. Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland
2. Section of Pulmonary and Critical Care, Dartmouth-Hitchcock Medical Center, Geisel School of Medicine, Hanover, New Hampshire
3. Division of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois, Chicago, Illinois
4. Department of Medicine and
5. Department of Physiology, University of California, Los Angeles, School of Medicine, Los Angeles, California
6. Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina
7. Division of Pulmonary and Critical Care, University of Utah School of Medicine, Salt Lake City, Utah
8. Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health, Denver, Colorado
9. Division of Pulmonary, Critical Care and Occupational Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
10. Division of Pulmonary and Critical Care, Temple University Hospital, Philadelphia, Pennsylvania
11. Division of Pulmonary, Allergy and Critical Care Medicine, Presbyterian Hospital, Columbia University Medical Center, New York, New York
12. Department of Internal Medicine, Weill Cornell Medical College, New York, New York
13. Division of Pulmonary and Critical Care Medicine, University of Michigan Health System, Ann Arbor, Michigan
14. Division of Pulmonary and Critical Care, Oaklawn Hospital, Marshall, Michigan
15. Center for Genomics and Personalized Medicine Research, Wake Forest University, Winston-Salem, North Carolina
16. Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama
17. Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, University of California, San Francisco, San Francisco, California; and
18. Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington