1. AGE Research Group, NIHR Newcastle Biomedical Research Centre, Newcastle University and Newcastle upon Tyne Hospitals Trust, Newcastle upon Tyne, UK
2. Molecular and Clinical Medicine, University of Dundee, Dundee, UK
3. Tayside Clinical Trials Unit, University of Dundee, Dundee, UK
4. Health Services Research Unit, University of Aberdeen, Aberdeen, UK
5. Cardiovascular and Respiratory Interface Section, National Heart and Lung Institute, Imperial College London, London, UK
6. Department of Medicine for the Elderly, NHS Tayside, Dundee, UK