[1] Northumbria Healthcare NHS Fdn Trust, Dept Geriatr Med, North Shields, England
[2] Newcastle Upon Tyne Hosp NHS Fdn Trust, Dept Med, Newcastle Upon Tyne, Tyne & Wear, England
[3] Univ Hosp South Manchester NHS Fdn Trust, Manchester, Lancs, England
[4] Univ Nottingham, Div Med Sci & Grad Entry Med, Derby, England
[5] City Univ London, Sch Hlth Sci, London, England