[1] Cardiff Univ, Marie Curie Palliat Care Res Ctr, Sch Med, Cardiff, S Glam, Wales
[2] Bangor Univ, Ctr Hlth Econ & Med Evaluat, Bangor, Gwynedd, Wales
[3] Univ Southampton, Southampton Clin Trials Unit, Southampton, Hants, England
[4] Univ Exeter, Med Sch, Exeter, Devon, England
[5] Cardiff Univ, Ctr Trials Res, Cardiff, S Glam, Wales
[6] Univ Bristol, Sch Social & Community Med, Bristol, Avon, England
[7] Doncaster & Bassetlaw NHS Fdn Trust, Doncaster Royal Infirm, Doncaster, England
[8] Univ Sheffield, Sch Nursing & Midwifery, Sheffield, S Yorkshire, England
[9] Leeds Inst Hlth Sci, Acad Unit Primary Care, Worsley Bldg,Room 10-35,Clarendon Way, Leeds LS2 9NL, W Yorkshire, England