1. Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
2. Department of Surgery and Cancer, Imperial College London, London, UK
3. Imperial Clinical Trials Unit, Imperial College London, London, UK
4. College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
5. Gloucestershire Hospitals NHS Foundation Trust, Gloucester, UK
6. Medical Research Council Population Health Research Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
7. Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
8. School of Health Sciences, University of Manchester, Manchester, UK
9. Department of Applied Economics, University of Granada, Granada, Spain
10. Worcestershire Acute Hospitals NHS Trust, Worcester, UK
11. North West London Hospitals NHS Trust, London, UK
12. Warwick Clinical Trials Unit, Warwick Medical School, University of Warwick, Coventry, UK