[1] Univ Oxford, Radcliffe Dept Med, Oxford, England
[2] Univ Oxford, Nuffield Dept Primary Care Hlth Sci, Oxford, England
[3] Oxford Hlth NHS Fdn Trust, Abingdon Hosp, Emergency Multidisciplinary Unit, Oxford, England
[4] Oxford Univ Hosp NHS Fdn Trust, Dept Geratol, London, England
[5] Imperial Coll London, Dept Publ Hlth & Primary Care, London, England
[6] Univ Oxford, Nuffield Dept Clin Neurosci, Ctr Prevent Stroke & Dementia, Oxford, England
[7] John Radcliffe Hosp, NIHR Oxford Biomed Res Ctr, Oxford, England
[8] Univ Oxford, Nuffield Dept Med, Oxford, England
[9] Univ Birmingham, Inst Appl Hlth Res, Coll Med & Dent Sci, Birmingham, W Midlands, England