Affiliation: | 1. Oesophageal Laboratory, Guys and St Thomas’ NHS Foundation Trust, , London, UK;2. Department of Gastroenterology, Guys and St Thomas’ NHS Foundation Trust, , London, UK;3. Information Services and Systems, King's College London, , London, UK;4. NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust, Queen's Medical Centre, , Nottingham, UK |