1. MRC Lifecourse Epidemiology Unit, Southampton General Hospital, University of Southampton, Southampton, UK;
2. School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, UK;
3. Population, Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, London, UK;
4. MRC Integrative Epidemiology Unit, Oakfield House, University of Bristol, Bristol, UK;
5. Department of Population Health Sciences, Oakfield House, Bristol, UK;
6. Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK