1. Division of Pulmonary, Critical Care, Hyperbaric, and Sleep Medicine, Department of Medicine, Loma Linda University, Loma Linda, California
2. Harvard Medical School, Boston, Massachusetts
3. Division of Pulmonary and Critical Care, Department of Medicine, Mount Auburn Hospital, Cambridge, Massachusetts
4. Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, New Haven, Connecticut
5. Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, South Carolina
6. Division of Pulmonary, Allergy and Critical Care Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
7. Division of Pulmonary, Critical Care, and Sleep Medicine, University of Washington, Seattle, Washington; and
8. Division of Pulmonary and Critical Care Medicine, University of Vermont, Burlington, Vermont