[1] Univ Edinburgh, Sch Hlth Social Sci, Clin Psychol, Edinburgh, Scotland
[2] Marie Curie Hosp Edinburgh, Edinburgh, Scotland
[3] Cardiff Univ, Marie Curie Res Ctr, Sch Med, Div Populat Med, Cardiff, Wales
[4] Univ Bristol, Bristol Med Sch, Palliat & End Life Care Res Grp, Populat Hlth Sci, Bristol, England
[5] Univ Chester, Chester, England
[6] North Tees & Hartlepool NHS Fdn Trust, Stockton On Tees, England
[7] Newcastle Univ, Populat Hlth Sci Inst, Fac Med Sci, Newcastle Upon Tyne, England