1. Department of Public Health and Primary Care; University of Cambridge School of Clinical Medicine, and Cambridge Biomedical Research Centre; Cambridge UK
2. Centre for Academic Primary Care; School of Social and Community Medicine; University of Bristol; Bristol UK
3. Barts NIHR Biomedical Research Unit; Queen Mary University of London; London Chest Hospital; London UK
4. Department of Emergency Medicine; James Paget University Hospital; Gorleston-on-Sea Norfolk
5. Department of Medicine; University of East Anglia; Norwich UK
6. Department of Epidemiology and Public Health; Clinical Epidemiology Group; University College London; London UK
7. School of Healthcare Sciences; Cardiff Metropolitan University