1. School of Medical Sciences, The University of Manchester, Manchester M13 9PL, UK
2. Department of Diabetes, Endocrinology and Obesity Medicine, Salford Royal Hospital, Northern Care Alliance NHS Foundation Trust, Salford M6 8HD, UK
3. Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PL, UK
4. Department of Oesophago-Gastric and Bariatric Surgery, Salford Royal Hospital, Northern Care Alliance NHS Foundation Trust, Salford M6 8HD, UK
5. School of Health and Society, Allerton Concourse, Frederick Road Campus, University of Salford, Salford M6 6PU, UK
6. Department of Bariatric, General, Gastrointestinal and Hepatobiliary Surgery, Burjeel Hospital, Al Najdah Street, Abu Dhabi P.O. Box 7400, United Arab Emirates