| Affiliation: | 1. Clinical Effectiveness Unit, Royal College of Surgeons of England, London, UK;2. St Helens and Knowsley Teaching Hospitals NHS Trust, Prescot, UK;3. Department of Health Services Research and Policy, Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, UK;4. Department of Epidemiology and Public Health, University College Cork, Cork, Ireland;5. James Paget University Hospitals NHS Foundation Trust, Great Yarmouth, UK;6. University of East Anglia, Norwich Research Park, Norwich, UK;7. Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Sheffield, UK;8. Portsmouth Hospitals NHS Trust, Queen Alexandra Hospital, Portsmouth, UK |
