University of Birmingham - Institute of Applied Health Research, University of Birmingham - MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham - School of Sport, Exercise and Rehabilitation Sciences, Newcastle University - AGE Research Group, Australian National University (ANU) - School of Demography, Centre de Recherche en Santé de Nouna, Centre de Recherche en Santé de Nouna, Stanford University - Division of Primary Care and Population Health, University College London, University of Lincoln (UK) - Lincoln International Institute for Rural Health, Harvard University - Center for Population and Development Studies, Centre de Recherche en Santé de Nouna, Centre de Recherche en Santé de Nouna, Burkina Faso and University of Birmingham - Institute of Applied Health Research