[1] Univ Cambridge, Inst Publ Hlth, Dept Publ Hlth & Primary Care, Primary Care Unit, Cambridge CB2 0SR, England
[2] Univ Manchester, Sch Nursing Midwifery & Social Work, Manchester M13 9PL, Lancs, England
[3] Kings Coll London, Sch Med, Div Hlth & Social Care Res, Dept Primary Care & Publ Hlth Sci, London SE1 3QD, England
[4] Kings Coll London, Inst Psychiat, London SE5 8AF, England
[5] Cambridge Univ Hosp NHS Fdn Trust, Addenbrookes Hosp, Palliat Care Team, Cambridge CB2 0QQ, England
[6] Kings Coll London, Cicely Saunders Inst, Dept Palliat Care Policy & Rehabil, London SE5 9PJ, England