1. Oregon Health & Science University, Portland, OR
2. California Pacific Medical Center Research Institute, San Francisco, CA
3. Department of Otolaryngology—Head and Neck Surgery, University of California, San Francisco, San Francisco, CA
4. Department of Psychiatry, University of California, San Diego, San Diego, CA
5. Dept. of Medicine, Harvard Medical School, Boston, MA
6. Departments of Medicine and Epidemiology & Community Health, University of Minnesota Medical School, Minneapolis, MN, and Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, MN