[1] Evelina London Childrens Hosp, Dept Paediat Surg, Level 4 Becket House,Lambeth Palace Rd, London SE1 7EH, England
[2] Kings Coll London, London, England
[3] Cent & North West London NHS Fdn Trust, London, England
[4] UCL, Marie Curie Palliat Care Res Dept, London, England
[5] Keele Univ, Sch Med, Med Educ, Keele, Staffs, England
[6] Cardiff Univ, Sch Med, Div Populat Med, Primary Care Patient Safety PISA Res Grp, Cardiff, S Glam, Wales
[7] Univ British Columbia, Dept Family Practice, Vancouver, BC, Canada
[8] Macquarie Univ, Fac Med & Hlth Sci, Australian Inst Hlth Innovat, Sydney, NSW, Australia
[9] London Sch Hyg & Trop Med, Dept Epidemiol & Populat Hlth, London, England