1. Royal Free Campus, Division of Surgery and Interventional Science, University College London, London, UK
2. Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, UK
3. Leeds Institute of Health Sciences, University of Leeds, Leeds, UK
4. Institute of Clinical and Applied Health Research, Faculty of Health Science, University of Hull, Hull, UK
5. Department of Applied Health Research, University College London, London, UK
6. Radiology, Royal Free Hospital, London, UK
7. Radiology, University College Hospital, London, UK
8. Cancer Institute, University College London, London, UK
9. Surgery and Transplantation, Leeds Teaching Hospital, Leeds, UK
10. General Surgery, Maastricht University, Maastricht, the Netherlands
11. Surgery, Radboud University Medical Centre, Nijmegen, the Netherlands