[1] Univ Bristol, Ctr Eth Med, Bristol, Avon, England
[2] Open Univ, Fac Hlth & Social Care, Milton Keynes, Bucks, England
[3] Univ Bath, Dept Social & Policy Sci, Bath, Avon, England
[4] Cardiff Univ, Coma & Disorders Consciousness Res Ctr, Cardiff, S Glam, Wales
[5] Univ Exeter, REACH Ctr Res Ageing & Cognit Hlth, Exeter, Devon, England