1. Department of Medicine, Imperial College London, London, UK;
2. Department of Medicine, Brighton and Sussex Medical School, Brighton, UK;
3. Department of Mathematics, University of Brighton, Brighton, UK;
4. Department of Neurology, The George Institute for Global Health, Sydney, Australia;
5. Division of Medicine Care of the Elderly Oulu City Hospital and Institute of Health Sciences (Geriatrics), Oulu University, Oulu, Finland
6. Department of Medicine, University of Leuven, Leuven, Belgium;
7. Department of Elderly Medicine, Brighton and Sussex University Hospital, Brighton, UK;