1. Department of Health and Human Services, Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
2. Department of Medicine, University of Pittsburgh, Pittsburgh, PA
3. Social & Scientific Systems, Inc., Research Triangle Park, NC
4. Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN
5. Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, MA
6. Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
7. Department of Epidemiology, Harvard School of Public Health, Boston, MA