[1] Univ Coll London UCL, Marie Curie Palliat Care Res Dept, Div Psychiat, London, England
[2] Univ Hosp Sussex NHS Fdn Trust, Worthing Hosp, Lyndhurst Rd, Worthing, England
[3] Univ Southampton, Southampton, England
[4] Univ Hosp Southampton NHS Foundat Trust, Southampton Gen Hosp, Southampton, England
[5] Univ Coll London UCL, Inst Epidemiol & Hlth Care, Fac Populat Hlth Sci, Dept Primary Care & Populat Hlth, London, England
[6] Univ Coll London UCL, Comprehens Clin Trials Unit, London, England