1. Leeds Institute of Medical Research at St James's, University of Leeds, Leeds, UK
2. Department of Anaesthetics, Guy's and St Thomas' Hospital, London, UK
3. Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
4. General Surgery Department, Vall d'Hebron University Hospital, Barcelona, Spain
5. Department of Surgery, Royal Free Hospital NHS Trust, London, UK
6. Centre for Medical Informatics, Usher Institute, University of Edinburgh, Edinburgh, UK
7. Department of Academic Surgery, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK