[1] Queens Univ Belfast, Wellcome Wolfson Inst Expt Med, Belfast, North Ireland
[2] Belfast Hlth & Social Care Trust, Royal Victoria Hosp, Belfast, North Ireland
[3] Northern Care Alliance NHS Fdn Trust, Manchester Ctr Clin Neurosci, Salford, England
[4] Kings Coll Hosp NHS Fdn Trust, Dept Neurol, London, England
[5] Queen Mary Univ London, Wolfson Inst Populat Hlth, Ctr Prevent Neurol, London, England
[6] Barts Hlth NHS Trust, Royal London Hosp, Dept Neurol, London, England