1. Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN
2. Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, MN
3. Department of Medicine, University of Minnesota, Minneapolis, MN
4. Department of Psychiatry, University of California-San Diego, La Jolla, CA
5. California Pacific Medical Center Research Institute, San Francisco, CA
6. Division of Sleep Medicine, Brigham and Women's Hospital and Beth Israel Deaconess Medical School, Harvard Medical School, Boston, MA