1. Department of Public Health, Epidemiology, and Health Economics; University of Liège, Quartier Hôpital; Liège Belgium
2. Division of Bone Diseases; Geneva University Hospitals and Faculty of Medicine; Geneva 14 Switzerland
3. Cartilage and Muscle Metabolism Unit and Chair of the Department of Public Health Sciences; CHU Liège; Liège Belgium
4. Gérontopôle de Toulouse, Institut du Vieillissement, Centre Hospitalo-Universitaire de Toulouse (CHU Toulouse); UMR INSERM 1027; University of Toulouse III; Toulouse France
5. Vrije Universiteit Brussel; Brussels Belgium
6. Geriatric Department; CHU Liège; Chénée Belgium