1. Department of Respiratory Medicine, Leeds Teaching Hospitals, Leeds, United Kingdom
2. Department of Respiratory Medicine, Belfast Health and Social Care Trust, Belfast, United Kingdom
3. Department of Radiology, Leeds Teaching Hospitals, Leeds, United Kingdom
4. Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, United Kingdom
5. Wolfson Institute of Population Health, Queen Mary University of London, London, United Kingdom
6. Leeds Diagnosis and Screening Unit, Leeds Institute of Health Sciences, University of Leeds, Leeds, United Kingdom