1. Glasgow University, Academic Section of Geriatric Medicine, Glasgow, UK
2. Glasgow Caledonian University, Nursing Midwifery and Allied Health Professions Research Unit, Glasgow, UK
3. University of Strathclyde, Bioengineering Unit, Wolfson Centre, Glasgow, UK
4. University of Edinburgh, Public Health Sciences, Edinburgh, UK
5. Glasgow Royal Infirmary, Academic Section of Geriatric Medicine, Glasgow Royal Infirmary, Glasgow, UK