1. Department of Health, Nutrition, and Exercise Sciences North Dakota State University Fargo North Dakota USA
2. California Pacific Medical Center Research Institute, San Francisco Coordinating Center San Francisco California USA
3. Department of Epidemiology and Biostatistics University of California, San Francisco San Francisco California USA
4. Geriatric Unit Fondazione IRCCS Caʼ Granda Ospedale Maggiore Policlinico Milan Italy
5. Department of Clinical Sciences and Community Health Università di Milano Milan Italy
6. Division of Rehabilitation Sciences University of Texas Medical Branch Galveston Texas USA
7. Ohio Musculoskeletal and Neurological Institute Athens Ohio USA
8. Department of Biomedical Sciences Ohio University Athens Ohio USA
9. Department of Geriatric Medicine Ohio University Athens Ohio USA