1. Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK;
2. Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK;
3. Department of Psychology, University of Edinburgh, Edinburgh, UK;
4. School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK;
5. Edinburgh Delirium Research Group, Geriatric Medicine Unit, University of Edinburgh, Edinburgh, UK;
6. Endocrinology Unit, University of Edinburgh, Edinburgh, UK