[1] Univ Bristol, Sch Social & Community Med, Surg Res Ctr, Bristol, Avon, England
[2] Univ Hosp Bristol NHS Fdn Trust, Div Surg Head & Neck, Bristol, Avon, England
[3] Derriford Hosp, Dept Upper Gastrointestinal Surg, Plymouth PL6 8DH, Devon, England
[4] Univ Bristol, Sch Social & Community Med, MRC ConDuCT Hub Collaborat & Innovat Difficult Co, Bristol, Avon, England
[5] Gastrooesophageal Support & Help GOSH, Bristol, Avon, England
[6] Univ Hosp Bristol NHS Fdn Trust, Bristol Haematol & Oncol Ctr, Bristol, Avon, England
[7] Imperial Coll NHS Trust, St Marys Hosp, Ctr Pathol, London, England
[8] Imperial Coll NHS Trust, St Marys Hosp, Dept Biosurg & Surg Technol, London, England