[1] Sheffield Hallam Univ, Ctr Hlth & Social Care Res, Sheffield, S Yorkshire, England
[2] Univ Sheffield, Acad Unit Surg Oncol, Sch Med, Sheffield, S Yorkshire, England
[3] Cardiff Univ, Sch Med, Div Populat Med, Cardiff, S Glam, Wales
[4] Cambridge Inst Publ Hlth, Biostat Unit, MRC, Cambridge, England
[5] Brighton & Sussex Med Sch, Brighton, E Sussex, England