1. Edinburgh Delirium Research Group, Geriatric Medicine; University of Edinburgh; Edinburgh UK
2. Centre for Cognitive Ageing and Cognitive Epidemiology; University of Edinburgh; Edinburgh Scotland
3. Oslo Delirium Research Group, Department of Geriatric Medicine; Oslo University Hospital; Oslo Norway
4. Institute of Basic Medical Sciences; University of Oslo; Oslo Norway
5. Centre for Public Health; Queen's University of Belfast; Belfast Ireland
6. Clinical Neurochemistry Laboratory; Sahlgrenska University Hospital; Mölndal Sweden
7. Department of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry; The Sahlgrenska Academy at the University of Gothenburg; Mölndal Sweden
8. Department of Molecular Neuroscience; UCL Institute of Neurology; London UK
9. Institute of Clinical Medicine; University of Oslo; Oslo Norway