1. NIHR Nottingham Biomedical Research Centre Nottingham University Hospitals NHS Trust and the University of Nottingham Nottingham UK
2. Nottingham Digestive Diseases Centre School of Medicine University of Nottingham Nottingham UK
3. Gastroenterology and Endoscopy Un V it Department of Pathophysiology and Transplantation Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Università degli Studi di Milano Milan Italy
4. Department for Targeted Intervention Division of Surgery & Interventional Science University College London (UCL) London UK