¹Guy’s & St Thomas’ NHS Foundation Trust, Gastroenterology, London, UK, ²Guy’s & St Thomas’ NHS Foundation Trust, Viapath Laboratories, London, UK

¹Department of Gastroenterology, Sheba Medical Center- Tel Hashomer, Ramat gan, Israel, ²Tel-Aviv University, Sackler School of Medicine, Tel Aviv, Israel, ³Department of Epidemiology and Preventive Medicine, School of Public Health, Tel Aviv, Israel, ⁴Department of Pediatric Gastroenterology, Sheba Medical Center- Tel Hashomer, Ramat gan, Israel

¹Gastroenterology, Mount Sinai Hospital, Toronto, Canada, ²General Surgery, Mount Sinai Hospital, Toronto, Canada, ³Centre for Global and Public Health, University of Manitoba, Winnepeg, Canada

¹Gastroenterologische Gemeinschaftspraxis Minden and University Hospital Schleswig-Holstein, Campus Kiel, Clinic for Internal Medicine I, Gastroenterology Practice, Minden, Germany, ²Competence-net IBD Germany, Study Department, Kiel, Germany, ³Competence-net IBD, Statistic Department, Kiel, Germany, ⁴Gastroenterology Practice Saarbrücken, Gastroenterology, Saarbrücken, Germany, ⁵Gastroenterology Practice Iserlohn, Gastroenterology, Iserlohn, Germany, ⁶Gastroentrology Practice Kassel, Gastroenterology, Kassel, Germany, ⁷University Hospital Erlangen, Gastroenterology Department, Erlangen, Germany, ⁸Gastroenterology Practice Herne, Gastroenterology, Herne, Germany, ⁹Gastroenterology Practice Berlin, Gastroenterology, Berlin, Germany, ¹⁰Gastroenterogy Practice Bremen, Gastroenterology, Bremen, Germany, ¹¹Gastroenterology Practice Mössingen, Gastroenterology, Mössingen, Germany, ¹³Competence-net IBD, Study Department, Kiel, Germany, ¹⁴Gastroenterology Practice Minden, Study Nurse, Minden, Germany, ¹⁵University Hospital Schleswig-Holstein- Campus Kiel- Clinic for Internal Medicine I, Gastroenterology Department, Kiel, Germany

Hospital Alemán, Department of Gastroenterology, Caba, Buenos Aires, Argentina

¹Aristotle University of Thessaloniki, Clinical research and Evidence-Based Medicine Unit, Thessaloniki, Greece, ²University of Oxford, Harris Manchester College, Oxford, UK

¹Gastroenterology, New York University School of Medicine, New York, USA, ²Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, USA, ³Gastroenterology, Weill Medical College of Cornell University, New York, USA, ⁴Gastroenterology, Albert Einstein College of Medicine, New York, USA, ⁵Gastroenterology, Hofstra Northwell School of Medicine, New York, USA, ⁶Columbia University Medical Center, Digestive and Liver Diseases, New York, USA, ⁷Gastroenterology, University of North Carolina School of Medicine, Chapel Hill, USA

¹CHU Amiens Sud, Service d’hepato-gastroentérologie, Amiens, France, ²APHM Hopital Nord, Hepato-gastroenterologie, Marseille, France, ³Hopital Haut Leveque, Hépato-gastroentérologie, Bordeaux, France, ⁴CHU Pontchaillou, Gastroenterologie, Rennes, France, ⁵Hopital Claude huriez, Gastroentérologie, Lille, France, ⁶Hôpital Saint Eloi, Gastroentérologie, Montpellier, France, ⁷Hopital Charles Nicolle, Gastroentérologie, Rouen, France, ⁸Hopital de l’Archet, Gastroentérologie, Nice, France, ⁹Policlinique Saint Claude, Gastroentérologie, Saint Quentin, France, ¹⁰Hopital universitaire, Gastroentérologie, Clermont Ferrand, France, ¹¹Hopital universitaire, Gastroentérologie, Besançon, France, ¹²CHU Amiens Sud, Statistique, Amiens, France

Royal Surrey NHS Foundation Trust, Department of Gastroenterology, Guildford, UK

¹Kyushu University, Department of Medicine and Clinical Science, Fukuoka, Japan, ²Kyushu University, Department of Epidemiology and Public Health, Fukuoka, Japan, ³Saga University Hospital, Department of Endoscopic Diagnostics and Therapeutics, Saga, Japan

¹Department of Gastroenterology, Yildirim Beyazit University Ankara, Turkey, ²Deparment of Gastroenterology, Ankara Sehir Hospital, Ankara, Turkey, ³Department of Gastroenterology, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey

¹Hospital Senhora da Oliveira, Gastroenterology, Guimarães, Portugal, ²Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga/Guimarães, Portugal, ³ICVS/3B’s, PT Government Associate Laboratory, Braga/Guimarães, Portugal

¹Aristotle University of Thessaloniki, Greece, Clinical Research and Evidence-Based Medicine Unit, Thessaloniki, Greece, ²Aristotle University of Thessaloniki, Clinical research and Evidence-Based Medicine Unit, Thessaloniki, Greece, ³Aristotle University of Thessaloniki, Second Propaideutic Department of Internal Medicine, Thessaloniki, Greece

¹Hospital Universitario De Canarias, Department of Digestive Service- Department of Gastroenterology, Santa Cruz De Tenerife, Spain, ²Hospital Universitario De Canarias, Department of Pharmacy, Santa Cruz De Tenerife, Spain

Hospital Universitario Ramón y Cajal, Servicio de Gastroenterología y Hepatología, Madrid, Spain

¹Department of Gastroenterology, Royal Free London NHS Trust, London, UK, ²Department of Hepatology, Royal Free London NHS Trust, London, UK

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

¹Department of Gastroenterology- Faculty of Medicine and Health, Örebro University, Örebro, Sweden, ²Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden, ³Clinical Epidemiology Division- Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden

¹Department of Gastroenterology, Hospital Alvaro Cunqueiro, University Hospital Complex of Vigo, Spain, ²University Hospital Complex of Vigo, Department of Gastroenterology, Vigo, Spain

¹University of Edinburgh, Child Life and Health, Edinburgh, UK, ²Royal Hospital for Sick Children, Paediatric Gastroenterology and Nutrition, Edinburgh, UK, ³Usher Institute, Centre for Medical Informatics, Edinburgh, UK, ⁴Royal Aberdeen Children’s Hospital, Paediatric Gastroenterology and Nutrition, Aberdeen, UK, ⁵Royal Hospital for Children, Paediatric Gastroenterology and Nutrition, Glasgow, UK, ⁶NHS National Services Scotland, Information Services Division, Edinburgh, UK, ⁷University of Edinburgh, Salvesen Mindroom Research Centre, Edinburgh, UK