1 WHO Collaborating Centre for Public Health Aspects of Musculo-Skeletal Health and Ageing, Division of Public Health, Epidemiology and Health Economics, University of Liège, CHU, Sart Tilman. Quartier Hôpital. Avenue Hippocrate 13 (Bât. B23), 4000, Liège, Belgium. dolores.sanchez@uliege.be.
2 Geriatrics Department, Hospital Del Mar Medical Research Institute (IMIM), Barcelona, Spain. dolores.sanchez@uliege.be.
3 Facultat de Ciències de la Salut i de la Vida, Universitat Pompeu Fabra, Barcelona, Spain. dolores.sanchez@uliege.be.
4 Rehabilitation Research Group, Hospital Del Mar Medical Research Institute (IMIM), Universitat Pompeu Fabra, Barcelona, Spain. dolores.sanchez@uliege.be.
5 Rehabilitation Research Group, Hospital Del Mar Medical Research Institute (IMIM), Universitat Pompeu Fabra, Barcelona, Spain.
6 Physical Medicine and Rehabilitation Department, Hospital Del Mar Medical Research Institute (IMIM), Barcelona, Spain.
7 Universitat International de Catalunya, Barcelona, Spain.
8 Facultat de Ciències de la Salut i de la Vida, Universitat Pompeu Fabra, Barcelona, Spain.
9 Department of Medicine, Medicine School, Universitat Autònoma de Barcelona, Barcelona, Spain.