¹Hospital Juan Ramón Jiménez, Gastroenterology Unit, Huelva, Spain, ²Universitary Hospital Virgen de Valme, Gastroenterology Unit, Seville, Spain, ³Universitary Hospital Virgen del Rocío, Gastroenterology Unit, Seville, Spain, ⁴Universitary Hospital Virgen de la Macarena, Gastroenterology Unit, Seville, Spain

¹University Erlangen-Nuremberg, Medical Clinic 1, Erlangen, Germany, ²Technical University of Munich, Clinic and Polyclinic for dermatology and allergology Biederstein, Munich, Germany, ³University Hospital of Giessen, Central Interdisciplinary Visceral Medical Endoscopy (ZIVE), Giessen, Germany, ⁴Hospital Helios Schwerin, Clinic for Gastroenterology and Infectiology, Schwerin, Germany, ⁵Hospital St. Marien Amberg, Clinic for Internal Medicine II, Amberg, Germany, ⁶Practice Clinic Schwabach, Schwabach, Germany, ⁷Hospital Neumarkt, Medical Clinic 2, Neumarkt, Germany

¹EMMS, Nazareth Hospital, Gastroenterology, Nazareth, Israel, ²EMMS, Nazarieth Hospital, Gastroenterology, Nazareth, Israel, ³Meir Medical Centre, Internal Medicine C, Kfar Saba, Israel, ⁴EMMS, Nazareth, Gastroenterology, Nazareth, Israel

¹Hospital Universitario Gregorio Marañón, Gastroenterology, Madrid, Spain, ²Miguel Hernández University, Medicine, Sant Joan, Alicante, Spain, ³Hospital Universitario A Coruña, Universidade da Coruña, INIBIC, Rheumatology, A Coruña, Spain, ⁴Clinic University Hospital, Internal Medicine, Valencia, Spain, ⁵Medical Affairs, Merck Sharp & Dohme, Madrid, Spain, ⁶Medical Affairs, Merck Sharp & Dohme, Spain, Madrid, Spain

¹Chulalongkorn University, Internal Medicine, Bangkok, Thailand, ²Siriraj Hospital, Internal Medicine, Bangkok, Thailand

¹Hospital Universitario Gregorio Marañón, Gastroenterology, Madrid, Spain, ²Miguel Hernández University, Medicine, Sant Joan, Alicante, Spain, ³Hospital Universitario A Coruña, Universidade da Coruña, INIBIC, Rheumatology, A Coruña, Spain, ⁴Clinic University Hospital, Internal Medicine, Valencia, Spain, ⁵Medical Affairs, Merck Sharp & Dohme, Madrid, Spain, ⁶Medical Affairs, Merck Sharp & Dohme, Spain, Madrid, Spain

¹Tel-Aviv Medical Center, IBD Center, Department of Gastroenterology and Liver Diseases, Tel Aviv, Israel, ²Tel-Aviv University, The Sackler Faculty of Medicine, Tel-Aviv, Israel, ³University of Haifa, School of Public Health, Haifa, Israel

¹Connolly Hospital and RCSI, Blanchardstown, Dublin 15, Department of Gastroenterology, Dublin, Ireland

¹Montpellier University Hospital, Gastroenterology, Montpellier, France, ²French Polynesia General Hospital, Gastroenterology, Papeete, French Polynesia, ³Montpellier University Hospital, Digestive Surgery, Montpellier, France

¹University of Southern Denmark, Research Unit of General Practice, Department of Public Health, Odense, Denmark, ²Odense University Hospital, Department of Medical Gastroenterology, Odense, Denmark, ³Institute of Clinical Research, Odense, Denmark

¹University of Melbourne, Department of Medicine, Melbourne, Australia, ²St Vincent's Hospital, Department of Gastroenterology, Melbourne, Australia, ³The Chinese University of Hong Kong, Department of Medicine and Therapeutics, Hong Kong, Hong Kong, ⁴The Chinese University of Hong Kong, Institute of Digestive Disease, State Key Laboratory of Digestive Diseases, Hong Kong, Hong Kong, ⁵The University of Queensland, Diamantina Institute, Faculty of Medicine, Translational Research Institute, Brisbane, Australia, ⁶The Chinese University of Hong Kong, Centre for Gut Microbiota Research, Hong Kong, Hong Kong

¹Yeungnam University College of Medicine, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Daegu, South Korea, ²Virginia Mason Medical Center, Digestive Disease Institute, Seattle, USA, ³Dongguk University College of Medicine, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kyeongju, South Korea

¹Umeå University, Department of medical bioscienses, clinical chemistry, Umeå, Sweden, ²Umeå University, Department of pharmacology and clinical neuroscience, Umeå, Sweden, ³Umeå University, Department of public health and clinical medicine, Umeå, Sweden

¹University of Rome 'Tor Vergata', Gastroenterology, Rome, Italy

¹Hospital Vall d′Hebron, Gastroenterology Department, Barcelona, Spain, ²Complejo Hospitalario de Pontevedra, Gastroenterology Unit, Pontevedra, Spain, ³Hospital Clínico Universitario, Unidad de Gastroenterología, Valencia, Spain, ⁴Hospital Universitario Puerta de Hierro, Servicio de Gastroenterologia, Madrid, Spain, ⁵Medical Department, MSD, Madrid, Spain, ⁶Hospital Universitari Germans Trias i Pujol, Gastroenterology Unit, Badalona, Spain, ⁷Spanish Association of patients with Crohn′s disease and Ulcerative colitis, Madrid, Spain, ⁸Institut Universitari Parc Taulí, Digestive Unit, Sabadell, Spain

¹Hvidovre University Hospital, The Paediatric Department, Hvidovre, Denmark, ²Hvidovre University Hospital, The GastroUnit, Hvidovre, Denmark, ³Herlev Hospital, The Department of Pathology, Herlev, Denmark, ⁴Tampere University Hospital, The Paediatric Department, Tampere, Finland

¹Bispebjerg and Frederiksberg Hospital, Center for Clinical Research and Prevention, Copenhagen, Denmark, ²University of Glasgow, Glasgow, UK, ³Bispebjerg and Frederiksberg Hospital, Abdominal Centre K, Copenhagen, Denmark

¹Janssen Immunology, Birkerød, Denmark, ²Janssen Immunology, High Wycombe, UK, ³Leo Pharma, Ballerup, Denmark, ⁴Incentive, Holte, Denmark, ⁵North Zealand University Hospital, Frederikssund, Denmark, ⁶Odense University Hospital, Odense, Denmark

¹Instituto de Investigación Sanitaria Galicia Sur. Hospital Alvaro Cunqueiro. EOXI Vigo, Gastroenterology, Vigo, Spain, ²Gentofte Hospital, Medical Gastroenterology, Copenhagen, Denmark, ³University Hospital Ioannina, 1st Division of Internal Medicine and Hepato-Gastroenterology Unit, Ioannina, Greece, ⁴State University of Medicine and Pharmacy of the Republic of Moldova, Gastroenterology, Chisinau, Moldova, Republic of, ⁵Morgagni Hospital, Gastroenterology and Digestive Endoscopy, Forli, Italy, ⁶Semmelweis University, 1st Department of Medicine, Budapest, Hungary, ⁷University of Medicine ‘Victor Babes’, Clinic of Gastroenterology, Timisoara, Romania, ⁸Moscow Regional Research Clinical Institute, Gastroenterology, Moscow, Russian Federation, ⁹Dronning Ingrids Hospital, Medical Department, Nuuk, Greenland, ¹⁰Lithuanian University of Health Sciences, Institute for Digestive Research, Kaunas, Lithuania, ¹¹Adelaide and Meath Hospital, Gastroenterology, Dublin, Ireland, ¹²Hospital Ceské Budejovice, Gastroenterology, Ceské Budejovice, Czech Republic, ¹³University Hospital Center Zagreb, Gastroenterology, Zagreb, Croatia, ¹⁴Hospital de São João, Porto; Institute of Pharmacology and Therapeutics, Oporto Medical School and Institute for molecular and cell biology, Gastroenterology, Porto, Portugal, ¹⁵21Landspitali - The National University Hospital of Iceland, Gastroenterology, Reykjavik, Iceland, ¹⁶Karolinska Institutet, GastroCentrum, Stockholm, Sweden, ¹⁷Amiens University and Hospital, Epimad Registry, Gastroenterology Unit, Amiens, France, ¹⁸Charles University, IBD Center ISCARE, Prague, Czech Republic, ¹⁹Herning Central Hospital, Medicine, Herning, Denmark, ²⁰Private Practice, Nicosia, Cyprus, ²¹Mater Dei Hospital, Gastroenterology, Msida, Malta, ²²St Vincent's Hospital, Gastroenterology, Melbourne, Australia, ²³AOU Careggi Regional Referral Center for Inflammatory Bowel Disease, Gastroenterology, Florence, Italy, ²⁴Soroka Medical Center and Ben Gurion University of the Negev, Gastroenterology and Hepatology, Beer Sheva, Israel, ²⁵Slagelse Hospital, Gastroenterology, Slagelse, Denmark, ²⁶Arhus University Hospital, Medicine V (Hepatology and Gastroenterology), Arhus, Denmark, ²⁷Tartu University Hospital, Endocrinology and Gastroenterology, Tartu, Estonia, ²⁸Azienda Ospedaliera di Padova, Surgery, Oncology and Gastroenterology, Padova, Italy, ²⁹Faculty of Medicine and Health, Gastroenterology, Orebro, Sweden, ³⁰Tampere University Hospital, Gastroenterology and Alimentary Tract Surgery, Tampere, Finland, ³¹St. Mark's Hospital, Imperial College London, Gastroenterology, London, UK, ³²The National Hospital of the Faroe Islands, Medical Department, Torshavn, Faroe Islands, ³³Regional Hospital of Viborg, Medical Department, Viborg, Denmark, ³⁴Hull and East Yorkshire NHS Trust, IBD Unit, Hull, UK, ³⁵North Zealand University Hospital, Gastroenterology, Frederikssund, Denmark

¹Cleveland Clinic, Colon and Rectal Surgery, Cleveland, USA, ²Cleveland Clinic, Quantitative Health Sciences, Cleveland, USA