1. Academic Unit of Elderly Care and Rehabilitation, University of Leeds and Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
2. Clinical Trials Research Unit, University of Leeds, Leeds, UK
3. Department of Stroke Medicine, Academic Neuroscience Centre P041, Institute of Psychiatry, King's College Hospital, London, UK
4. CEMH, Institute of Psychiatry, London, UK
5. PSSRU, London School of Economics, London, UK