¹The sixth hospital affiliated to sun yat-sen university, Gastroenterology dept., Guangzhou, China

¹Bispebjerg and Frederiksberg Hospital, Center for Clinical Research and Prevention, Frederiksberg, Denmark, ²Statens Serum Institut, Department of Epidemiology Research, Copenhagen, Denmark

¹Icahn School of Medicine at Mount Sinai Hospital, Department of Genetics and Genomic Sciences, New York, USA, ²Icahn School of Medicine at Mount Sinai Hospital, Department of Environmental Medicine and Public Health, New York, USA, ³Hospital Beatriz Ângelo, Surgical Department, Gastroenterology Division, Loures, Portugal, ⁴Icahn School of Medicine at Mount Sinai Hospital, Division of Gastroenterology, Department of Medicine, New York, USA

¹ASST Rhodense, Rho, Italy

¹University of Montreal, Montreal, Canada, ²CHU Sainte-Justine, Department of Pediatrics, Unit of Gastroenterology, Montreal, Canada, ³Research center CHU Sainte Justine, Montreal, Canada

¹University of Ulsan College of Medicine, Asan Medical Center, Department of Gastroenterology, Seoul, South Korea, ²University of Ulsan College of Medicine, Asan Medical Center, Department of Biochemistry, Seoul, South Korea, ³University of Ulsan College of Medicine, Asan Medical Center, Department of Clinical Epidemiology and Biostatistics, Seoul, South Korea

¹Seoul National University College of Medicine, Department of Internal Medicine and Liver Research Institute, Seoul, South Korea, ²College of Medicine, The Catholic University of Korea, Department of Biostatistics, Seoul, South Korea

¹Institut Universitari Parc Taulí, Digestive Unit, Sabadell, 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, ⁵Hospital Universitari Germans Trias i Pujol, Gastroenterology Unit, Badalona, Spain, ⁶Spanish Association of patients with Crohn′s disease and Ulcerative colitis, Madrid, Spain, ⁷Medical Department, MSD, Madrid, Spain, ⁸Hospital Vall d′Hebron, Gastroenterology Department, Barcelona, Spain

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