[1] UCL Royal Free & Univ Coll Med Sch, Dept Mental Hlth Sci, Marie Curie Palliat Care R&D Unit, London NW3 2PF, England
[2] Univ Southampton, Hlth Care Res Unit, Southampton SO9 5NH, Hants, England
[3] Univ Sheffield, Trent Palliat Care Res Grp, Sheffield, S Yorkshire, England