1. Department of Veterans Affairs, Puget Sound Health Care System, Health Services R&D, Seattle, Washington, USA.
2. Department of Veterans Affairs, Portland Health Care System, Health Services R&D, Portland, Oregon, USA.
3. Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health and Science University, Portland, Oregon, USA.
4. Department of Veterans Affairs, Division of Pulmonary and Critical Care Medicine, Birmingham VA Medical Center, Birmingham, Alabama, USA.
5. Division of Pulmonary, Allergy, and Critical Care Medicine, Lung Health Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.
6. Geriatric and Palliative Care Medicine Division, School of Medicine, University of Washington, Seattle, Washington, USA.
7. Pulmonary and Critical Care Medicine Division, School of Medicine, University of Washington, Seattle, Washington, USA.