¹Azienda Ospedaliera Consorziale Policlinico, Bari, Italy, ²University of Bari, DETO, Bari, Italy, ³Sanitanova SRL, Milan, Italy, ⁴University of Bari, Department of Emergency and Organ Transplantation, Bari, Italy

¹Gastroenterology Department, Hospital Universitario Gregorio Marañón, Madrid, Spain, ²Gastroenterology Department, Hospital Universitario Vall d'Hebron, Barcelona, Spain, ³Merck Sharp and Dohme, Spain, Medical Affairs, Madrid, Spain

¹Corporal Michael J. Crescenz, VA Medical Center, Gastroenterology, Philadelphia, USA, ²University of Pennsylvania, Perelman School of Medicine, Gastroenterology, Philadelphia, USA

¹Ist Dept of Pediatrics, Semmelweis University, Budapest, Hungary, ²Ist Dept of Pediatrics, Semmelweis Universtiy, Budapest, Hungary

¹Seoul National University College of Medicine, Preventive Medicine, Seoul, South Korea, ²Gangnam Severance Hospital, Yonsei University College of Medicine, Internal Medicine, Seoul, South Korea, ³Severance Hospital, Yonsei University College of Medicine, Internal Medicine, Seoul, South Korea

¹Gastroenterology Department, Hospital Universitario Vall d'Hebron, Barcelona, Spain, ²Gastroenterology Department, Hospital Universitario Gregorio Marañón, Madrid, Spain, ³Rheumatology Department, Hospital Universitario A Coruña, Universidade da Coruña, INIBIC, A Coruña, Spain, ⁴Internal Medicine Department, Hospital Clínico de Valencia, Valencia, Spain, ⁵Merck Sharp and Dohme, Spain, Medical Affairs, Madrid, Spain, ⁶Department of Medicine, Miguel Hernández University, Sant Joan, Alicante, Spain

¹Kyungpook National University School of Medicine, Intermal Medicine, Daegu, South Korea, ²Yeungnam University College of Medicine, Internal Medicine, Daegu, South Korea, ³Keimyung University School of Medicine, Internal Medicine, Daegu, South Korea, ⁴Catholic University of Daegu School of Medicine, Internal Medicine, Daegu, South Korea, ⁵Dongguk University School of Medicine, Internal Medicine, Daegu, South Korea

¹Team Gesundheit GmbH, Essen, Germany, ²Takeda Pharma Vertrieb GmbH, Berlin, Germany

¹Rabin Medical Center, Division of Gastroenterology, Petah-Tikva, Israel, ²Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv, Israel, ³Tel Aviv Sourasky Medical Center, Proctology Unit, Department of Surgery, Tel Aviv, Israel

¹King's College Hospital NHS Foundation Trust, Paediatric Gastroenterology, Hepatology and Nutrition, London, UK, ²King's College Hospital NHS Foundation Trust, London, UK

University Hospital Ulm, Department of Internal Medicine I, Ulm, Germany

¹Yeungnam University College of Medicine, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Daegu, South Korea, ²Dongguk University Collge of Medicine, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kyungju, South Korea

¹University Hospital of Heraklion, Department of Gastroenterology, Heraklion, Greece, ²Evangelismos Hospital, Gastroenterology Unit, Athens, Greece, ³Venizeleion General Hospital, Department of Gastroenterology, Heraklion, Greece

¹Hospital Universitario de Fuenlabrada, Gastroenterology, Fuenlabrada, Spain, ²Hospital Universitario de Fuenlabrada, Pharmacy, Fuenlabrada, Spain, ³Hospital Universitario de Fuenlabrada, Radiology, Fuenlabrada, Spain

¹Imperial College London, Department of Surgery and Cancer, London, UK, ²St Mark's Hospital and Academic Institute, Surgical Epidemiology Trials and Outcome Centre, London, UK, ³Karolinska Institutet, Department of Molecular Medicine and Surgery, Stockholm, Sweden, ⁴Karolinska University Hospital, Center for Digestive Disease, Division of Coloproctology, Stockholm, Sweden, ⁵University Hospitals Birmingham, Academic Department of Surgery, Birmingham, UK, ⁶St Mark's Hospital and Academic Institute, London, UK, ⁷Karolinska Institutet, Clinical Epidemiology Unit, Department of Medicine, Stockholm, Sweden, ⁸Karolinska Institutet, Sachs’ Children and Youth Hospital, Stockholm South General Hospital, and Department of Clinical Science and Education Södersjukhuset, Stockholm, Sweden, ⁹Karolinska Institutet, Unit of Biostatistics, Institute of Environmental Medicine, Stockholm, Sweden, ¹⁰Linköping University, Division of Surgery, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping, Sweden, ¹¹County Council of Östergötland, Department of Surgery, Linköping, Sweden

¹North Zealand University Hospital, Department of Gastroenterology, Frederikssund, Denmark, ²Mater Dei Hospital, Division of Gastroenterology, L-Imsida, Malta, ³St Mark's Hospital, Gastroenterology, London, UK, ⁴Nicosia Private practice, Nicosia Private practice, Nicosia, Cyprus, ⁵Azienda Ospedaliera di Padova, Department of Surgery, Oncology and Gastroenterology, Padova, Italy, ⁶Viborg Regional Hospital, Medical Department, Viborg, Denmark, ⁷Hospital of Southern Jutland, Medical Department, Aabenraa, Denmark, ⁸Moscow Regional Research Clinical Institute, Department of Gastroenterology, Moscow, Russian Federation, ⁹Complexo Hospitalario Universitario de Vigo, Gastroenterology Department, Vigo, Spain, ¹⁰Semmelweis University, 1st Department of Medicine, Budapest, Hungary, ¹¹State University of Medicine and Pharmacy of the Republic of Moldova, Department of Gastroenterology, Chisinau, Moldova, Republic of, ¹²University of Porto, Institute for molecular and cell biology, Porto, Portugal, ¹³Hospital de São João, Department of Gastroenterology, Porto, Portugal, ¹⁴Oporto Medical School, Institute of Pharmacology and Therapeutics, Porto, Portugal, ¹⁵Lithuanian University of Health Sciences, Institute for Digestive Research, Kaunas, Lithuania, ¹⁶Faculty of Medicine and Health, Örebro University, Department of Gastronterology, Örebro, Sweden, ¹⁷Charles University, IBD Center ISCARE, Prague, Czech Republic, ¹⁸Herning Central Hospital, Department of medicine, Herning, Denmark, ¹⁹University of Medicine ‘Victor Babes’, Clinic of Gastroenterology, Timisoara, Romania, ²⁰Aarhus University Hospital, Department of Hepatology and Gastroenterology, Aarhus, Denmark, ²¹Tampere University Hospital, Department of Gastroenterology and Alimentary Tract Surgery, Tampere, Finland, ²²University Hospital Center Zagreb, University of Zagreb School of Medicine, Division of Gastroenterology and Hepatology, Zagreb, Croatia, ²³Amiens University and Hospital, Epimad Registry, Gastroenterology Unit, Amiens, France, ²⁴Soroka Medical Center and Ben Gurion University of the Negev, Department of Gastroenterology and Hepatology, Beer Sheva, Israel, ²⁵The National Hospital of the Faroe Islands, Medical department, Tórshavn, Faroe Islands, ²⁶Department of Gastroenterology and Digestive Endoscopy, Morgagni Hospital, Forli, Italy, ²⁷Slagelse Hospital, Department of Gastroenterology, Slagelse, Denmark, ²⁸AOU Careggi Regional Referral Center for Inflammatory Bowel Disease, Gastroenterology Department, Florence, Italy, ²⁹Tartu University Hospital, Division of Endocrinology and Gastroenterology, Tartu, Estonia, ³⁰University Hospital, Ioannina, 1st Division of Internal Medicine and Hepato-Gastroenterology Unit, Ioannina, Greece, ³¹Gentofte Hospital, Department of Medical Gastroenterology, Copenhagen, Denmark

Gastrounit, Hvidovre Hospital, Gastroenterology, Copenhagen, Denmark

¹University Medical Center Groningen, Gastroenterology and Hepatology, Groningen, The Netherlands, ²University Medical Center Groningen, Epidemiology, Groningen, The Netherlands, ³University Medical Center Groningen, Genetics, Groningen, The Netherlands, ⁴University Medical Center Groningen, Medical Microbiology, Groningen, The Netherlands

¹University Medical Center Groningen, Gastroenterology and Hepatology, Groningen, The Netherlands, ²University Medical Center Groningen, Epidemiology, Groningen, The Netherlands

¹Oslo University Hospital, Department of Gastroenterology, Oslo, Norway, ²University of Oslo, Department of Nursing Science, Oslo, Norway, ³Akershus University Hospital, Department of Gastroenterology, Nordbyhagen, Norway, ⁴Telemark Hospital Trust, Skien, Skien, Norway, ⁵Oslo University Hospital, Department of Pediatrics, Oslo, Norway, ⁶Akershus University Hospital, Department of Pediatrics, Nordbyhagen, Norway, ⁷Diakonhjemmet Hospital, Department of Gastroenterology, Oslo, Norway, ⁸Lovisenberg Diaconal Hospital, Department of Medicine, Oslo, Norway, ⁹Innlandet Hospital Trust Kongsvinger, Kongsvinger, Norway, ¹⁰Innlandet Hospital Trust Lillehammer, Pediatric Department, Lillehammer, Norway, ¹¹Innlandet Hospital Trust Elverum, Department of Medicine, Elverum, Norway, ¹²Innlandet Hospital Trust Elverum, Department of Pediatrics, Elverum, Norway, ¹³Sykehuset Innlandet Hamar, Department of Medicine, Hamar, Norway, ¹⁴Innlandet Hospital Trust Gjøvik, Department of Medicine, Gjøvik, Norway, ¹⁵University of Oslo, Oslo, Norway, ¹⁶Vestre Viken Hospital Trust Bærum, Department of Gastroenterology, Bærum, Norway, ¹⁷Vestre Viken Hospital Trust Drammen, Department of Pediatric and Adolescent Medicine, Drammen, Norway, ¹⁸Vestre Viken Hospital Trust Kongsberg, Department of Medicine, Kongsberg, Norway, ¹⁹Vestfold Hospital Trust, Tonsberg, Department of Pediatrics, Tonsberg, Norway, ²⁰Telemark Hospital Trust Skien, Department of Pediatrics, Skien, Norway, ²¹Telemark Hospital Trust Notodden, Department of Medicine, Notodden, Norway, ²²Østfold Hospital Trust, Department of Gastroenterology, Grålum, Norway, ²³Østfold Hospital Trust, Department of Pediatrics, Grålum, Norway, ²⁴Institute of Public Health, Oslo, Norway, ²⁵Sørlandet Hospital Kristiansand, Department of Gastroenterology, Kristiansand, Norway, ²⁶Sørlandet Hospital Arendal, Department of Gastroenterology, Arendal, Norway, ²⁷Sørlandet Hospital Arendal, Department of Pediatrics, Arendal, Norway, ²⁸Sørlandet Hospital Flekkefjord, Department of Medicine, Flekkefjord, Norway