1. Johns Hopkins University School of Medicine; Baltimore Maryland U.S.A.
2. Drexel University College of Medicine; Philadelphia Pennsylvania U.S.A.
3. Center on Aging and Health; Johns Hopkins Medical Institutions; Baltimore Maryland U.S.A.
4. University of Oklahoma College of Medicine; Oklahoma City Oklahoma U.S.A.
5. Departments of Otolaryngology-Head & Neck Surgery; Geriatric Medicine, Mental Health and Epidemiology, Johns Hopkins University; Baltimore Maryland U.S.A.