¹Department of Gastroenterology, Western General Hospital, The Edinburgh IBD Unit, Edinburgh, UK, ²Department of Gastroenterology, University Hospital Hairmyres, Glasgow, UK, ³Department of Gastroenterology, Ninewells Hospital, Dundee, UK, ⁴Department of Gastroenterology, Royal Alexandra Hospital, Glasgow, UK, ⁵Department of Gastroenterology, Aberdeen Royal Infirmary, Aberdeen, UK, ⁶Department of Gastroenterology, Glasgow Royal Infirmary,Glasgow, UK, ⁷Department of Gastroenterology, Victoria Hospital, Kirkcaldy, UK, ⁸Department of Gastroenterology, Forth Valley Royal Hospital, Larbert, UK, ⁹Department of Gastroenterology, Queen Elizabeth University Hospital, Glasgow, UK, ¹⁰Department of Gastroenterology, Royal Alexandra Hospital, Paisley, UK

¹Evangelismos Hospital, Department of Gastroenterology, Athens, Greece, ²University Hospital and Medical School of Ioannina, Gastroenterology, Ioannina, Greece

Hospital Universitario Virgen de las Nieves, Gastroenterology, Granada, Spain

¹Amsterdam University Medical Centers, Departmenn of Gastroenterology and Hepatology, Amsterdam, The Netherlands, ²Hvidovre Hospital, Gastrounit- Division of Medicine, Copenhagen, Denmark, ³Humanitas University, Gastroenterology, Milan, Italy, ⁴University of Calgary, Medicine- Division of Gastroenterology, Calgary, Canada, ⁵University Teaching Hospital Lueneburg, Gastroenterology, Lueneburg, Germany

¹University of Liverpool, Institute of Translational Medicine, Liverpool- UK, UK, ²Royal Liverpool University Hospitals Trust, Gastroenterology, Liverpool, UK, ³Wirral University Teaching Hospital NHS Foundation Trust, Gastroenterology, Wirral, UK, ⁴Rowett Institute of Nutrition and Health, Biomathematics and Statistics Scotland, Aberdeen, UK, ⁵Newcastle upon Tyne Hospitals NHS Foundation Trust, Gastroenterology, Newcastle upon Tyne, UK, ⁶Cambridge University Hospitals NHS Foundation Trust, Gastroenterology, Cambridge, UK, ⁷St Mark’s Hospital- Harrow, Gastroenterology, London, UK, ⁸James Cook University Hospital, Gastroenterology, Middlesbrough, UK, ⁹Queen Elizabeth Hospital Birmingham NHS Foundation Trust, Gastroenterology, Birmingham, UK, ¹⁰Shrewsbury and Telford Hospital NHS Trust, Gastroenterology, Shrewsbury, UK, ¹¹University of Liverpool, Liverpool Cancer Trials Unit, Liverpool, UK

¹Mersin University Faculty of Medicine, Gastroenterology, Mersin, Turkey, ²Didim State Hospital, İnternal Medicine, Aydın, Turkey, ³Mersin University Faculty of Medicine, Biostatistics, Mersin, Turkey

¹University Hospital Zurich, Department of Gastroenterology and Hepatology, Zurich, Switzerland, ²University Hospital Zurich, Department of Surgery and Transplantation, Zurich, Switzerland

¹Department of Gastroenterology, Queen Elizabeth University Hospital, Glasgow, UK, ²Department of Biochemistry, Queen Elizabeth University Hospital, Glasgow, UK

¹St Mark’s Hospital, IBD Unit, London, UK, ²St Mark’s Hospital, Intestinal Failure, London, UK

¹Hosp. Universitario Nuestra Señora de la Candelaria, Gastroenterology, Santa Cruz de Tenerife, Spain, ²Hospital Universitario Puerta de Hierro, Gastroenterology, Madrid, Spain, ³Complexo Hospitalario Universitario de Pontevedra, Gastroenterology, Pontevedra, Spain, ⁴Hospital Universitario Germans Trias i Pujol, Gastroenterology, Badalona, Spain, ⁵Hospital General de Tomelloso, Gastroenterology, Tomelloso, Spain, ⁶Hospital Clínico San Carlos, Gastroenterology, Madrid, Spain, ⁷Hospital Reina Sofía, Gastroenterology, Córdoba, Spain, ⁸Hospital Universitario Marqués de Valdecilla, Gastroenterology, Santander, Spain, ⁹Hospital Universitari de Bellvitge, Gastroenterology, Barcelona, Spain, ¹⁰Hospital Universitario Ramón y Cajal, Gastroenterology, Madrid, Spain, ¹¹Hospital Universitario Río Hortega, Gastroenterology, Valladolid, Spain, ¹²Complexo H. Universitario de Vigo, Gastroenterology, Vigo, Spain, ¹³Hospital Universitari La Fe de Valencia and CIBEREHD, Gastroenterology, Valencia, Spain, ¹⁴Hospital Universitari Mútua Terrassa and CIBEREHD, Gastroenterology, Barcelona, Spain, ¹⁵Hospital de Galdakao, Gastroenterology, Galdakao, Spain, ¹⁶Hospital Universitari de Girona, Gastroenterology, Girona, Spain, ¹⁷Hospital de la Sta Creu i Sant Pau, Gastroenterology, Barcelona, Spain, ¹⁸Complejo Asistencial Universitario de León, Gastroenterology, León, Spain, ¹⁹Hospital General Universitario de Valencia, Gastroenterology, Valencia, Spain, ²⁰Hospital Universitario de Donostia- Instituto Biodonostia- Universidad del País Vasco UPV/EHU- and CIBEREHD, Gastroenterology, Donostia, Spain, ²¹Hospital Universitario Central de Asturias, Gastroenterology, Oviedo, Spain, ²²Hospital de Cruces, Gastroenterology, Barakaldo, Spain, ²³Hospital Universitario Germans Trias i Pujol and CIBEREHD, Gastroenterology, Badalona, Spain, ²⁴Hospital Universitario de Canarias, Gastroenterology, La Laguna, Spain

¹Justus-Liebig-Universität, Institute of Nutritional Science, Giessen, Germany, ²Interdisciplinary Crohn-Colitis Centre Rhein-Main, Clinical and Scientific Research, Frankfurt am Main, Germany, ³J.W. Goethe University, Institute of Pharmaceutical Chemistry, Frankfurt am Main, Germany, ⁴Hacettepe University, Institute of Science, Ankara, Turkey, ⁵Hacettepe University, Institute of Nutritional Science, Ankara, Turkey, ⁶Agaplesion Markus Krankenhaus, Gastroenterology, Frankfurt am Main, Germany, ⁷DGD Clinics Sachsenhausen, Gastroenterology and Clinical Nutrition, Frankfurt am Main, Germany

¹University of New South Wales, South Western Sydney Clinical School, Sydney, Australia, ²St Vincent’s Hospital, Department of Gastroenterology and Hepatology, Sydney, Australia, ³Liverpool Hospital, Department of Gastroenterology and Hepatology, Sydney, Australia, ⁴Royal Prince Alfred Hospital, Department of Gastroenterology and Hepatology, Sydney, Australia, ⁵Ingham Institute for Applied Medical Research, South Western Sydney Clinical School, Sydney, Australia, ⁶Concord Repatriation General Hospital, Department of Gastroenterology and Hepatology, Sydney, Australia

¹University of British Columbia, Department of Pediatric Gastroenterology, Vancouver, Canada, ²University of Alberta, Department of Pediatric Gastroenterology, Edmonton, Canada, ³University of Manitoba, Department of Pediatric Gastroenterology, Winnipeg, Canada, ⁴University of Calgary, Section of Pediatric Gastroenterology, Calgary, Canada

¹Department of Gastroenterology, Azienda Sanitaria Universitaria Integrata di Udine, Udine, Italy, ²Istituto di Patologia Clinica, Azienda Sanitaria Universitaria Integrata di Udine, Udine, Italy

Department of Gastroenterology, Royal United Hospitals Bath NHS Foundation Trust, Bath, UK

Beaumont Hospital, Department of Gastroenterology, Dublin, Ireland

University Hospital Complex of Vigo, Department of Gastroenterology, Vigo, Spain

Moscow Scientific Center named after A. S. Loginov, Department of IBD, Moscow, Russian Federation

¹Faculty of Medicine of Tunis, Gastroenterology A Rabta, Tunis, Tunisia, ²Rabta, Gastroenterology A, Tunis, Tunisia

¹National and Kapodistrian University of Athens, GI Unit-3rd Academic Department of Internal Medicine- Sotiria Hospital, Athens, Greece, ²Medical School-National and Kapodistrian University of Athens, 2nd Department of Surgery Aretaieion Hospital, Athens, Greece, ³National and Kapodistrian University of Athens- Medical School, Gastroenterology Department of Laiko Hospital, Athens, Greece