1. San Francisco Veterans Affairs Medical Center, San Francisco, California;
2. Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine,
3. Department of Global Health, University of Washington, Seattle, Washington; and
4. Philip R. Lee Institute for Health Policy Studies,
5. Department of Epidemiology and Biostatistics, and
6. Department of Medicine, University of California San Francisco, San Francisco, California;
7. Measurement Science Quality Enhancement Research Initiative, San Francisco Veterans Affairs Healthcare System, San Francisco, California