1. Center for Health Research; Geisinger Health System; Danville PA
2. Krieger School of Arts and Sciences; Johns Hopkins University; Baltimore MD
3. Department of Otolaryngology-Head and Neck Surgery; Feinberg School of Medicine, Northwestern University; Chicago IL
4. Department of Otolaryngology-Head and Neck Surgery; Geisinger Health System; Danville PA
5. Department of Environmental Health Sciences; Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University; Baltimore MD
6. Department of Epidemiology; Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University; Baltimore MD