1. Section of Public Health, School of Health and Related Research, University of Sheffield, Regent Court, 30 Regent Street, Sheffield, S1 4DA, UK,
2. Sheffield Institute for Studies on Ageing, University of Sheffield, Elmfield, Northumberland Road, Sheffield, S10 2TU, UK
3. International Observatory on End of Life Care, Institute of Health Research, University of Lancaster, Bowland Tower East, Lancaster, LA1 4YT, UK
4. Nottingham Primary Care Research Partnership, Research and Development Department, Hucknall Health Centre, Nottingham, NG15 5JE, UK
5. The Peninsula Medical School, University of Exeter, The John Bull Building, Tamar Science Park, Research Way, Plymouth, PL6 8BU, UK
6. Faculty of Medicine, UAE University, Al Ain, United Arab Emirates
7. School of Health Studies, University of Bradford, 25 Trinity Road, Bradford, BD5 0BB, UK