1. Department of Gastroenterology, University Hospital of Coventry and Warwickshire, Coventry CV2 2DX, UK
2. CorporateHealth International, Inverness IV2 5NA, UK
3. Mathematics and Computer Science Department, The University of Barcelona, 58508007 Barcelona, Spain
4. Institute of Applied Health Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK
5. Department of Gastroenterology, Odense University Hospital & Svendborg Sygehus, 5700 Odense, Denmark
6. Department of Clinical Research, University of Southern Denmark (SDU), 5000 Odense, Denmark
7. Department of Social Medicine and Public Health, Pomeranian Medical University, 70-204 Szczecin, Poland
8. Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
9. Department of Gastroenterology, Leicester Cancer Centre, University of Leicester, Leicester LE1 7RH, UK