¹Tallaght University Hospital, Department of Gastroenterology, Dublin 24, Ireland, ²Trinity College Dublin, School of Medicine, Dublin 2, Ireland

¹Juntendo University School of Medicine, Department of Gastroenterology, Tokyo, Japan, ²Juntendo University Urayasu Hospital, Department of Gastroenterology, Urayasu, Japan

¹Great Ormond Street Hospital, Gastroenterology, London, UK

¹Severance Children's Hospital, Department of pediatrics, Seoul, South Korea

¹P D Hinduja Hospital, Biochemistry, Mumbai, India, ²P D Hinduja Hospital, Gastroenterology, Mumbai, India, ³Projection Research, Phoenixville, PA. 19460, USA

¹Royal Liverpool University Hospital, Gastroenterology, Liverpool, UK, ²Aintree University Hospital, Gastroenterology, Liverpool, UK, ³Arrowe Park Hospital, Gastroenterology, Upton, UK, ⁴Countess of Chester Hospital, Gastroenterology, Chester, UK

¹Inselspital / University hospital Bern, Bern, Switzerland

¹University of Cambridge, Department of Medicine, Cambridge, UK, ²Addenbrooke's Hospital, Pharmacy, Cambridge, UK

¹University of Leuven, Department of Pharmaceutical and Pharmacological Sciences, Leuven, Belgium, ²University Medical Centre Ljubljana, Department of Gastroenterology and Hepatology, Ljubljana, Slovenia, ³University Hospitals Leuven, Department of Gastroenterology and Hepatology, Leuven, Belgium, ⁴University of Leuven, Department of Chronic Diseases, Metabolism and Ageing, Leuven, Belgium

¹University of North Carolina, Medicine, Chapel Hill, USA, ²OpenBiome, Somerville, MA, USA, ³Finch, Somerville, MA, USA

¹Leiden University Medical Center, Gastroenterology and Hepatology, Leiden, The Netherlands, ²Leiden University Medical Center, Dietetics, Leiden, The Netherlands, ³Voeding Leeft, Amsterdam, The Netherlands

¹Amsterdam UMC, Department of Surgery, Amsterdam, The Netherlands, ²Amsterdam UMC, Department of Gastroenterology and Hepatology, Amsterdam, The Netherlands

¹Medical University of Graz, Graz, Austria, ²Barmherzige Brüder St. Veit/Glan, St. Veit, Austria

¹University of Michigan, Pediatric Gastroenterology, Ann Arbor, USA, ²University of Michigan, Child Health Evaluation and Research (CHEAR) Center, Ann Arbor, USA, ³University of Michigan, Health Services Research Program, Department of Neurology, Ann Arbor, USA, ⁴University of Michigan, Pediatric Surgery, Ann Arbor, USA

¹Erasmus Medical Center - Sophia Children's Hospital, Paediatric gastroenterology, Rotterdam, The Netherlands, ²Centre for Immunobiology, Blizard Institute, Barts and the London School of Medicine, Queen Mary University of London, Paediatric gastroenterology, London, UK, ³Université Paris Descartes, Sorbonne Paris Cité, APHP, Hôpital Necker Enfants Malades, Paediatric gastroenterology, Paris, France

¹Amsterdam UMC - location AMC, Hospital Pharmacy, Amsterdam, The Netherlands, ²Amsterdam UMC - location AMC, Gastroenterology and Hepatology, Amsterdam, The Netherlands, ³Sanquin Diagnostic Services, Biologics Lab, Bioanalysis, Amsterdam, The Netherlands

¹Center for Diagnostic and Therapeutic Endoscopy, School of Medicine, Keio University, Tokyo, Japan, ²AbbVie GK, Tokyo, Japan, ³Center for Advanced IBD Research and Treatment, Kitasato Institute Hospital, Kitasato University, Tokyo, Japan

¹King's College London, Department of Nutritional Sciences, London, UK, ²Guy's and St Thomas' NHS Foundation Trust, Department of Gastroenterology, London, UK, ³Guy's and St Thomas' NHS Foundation Trust, London, UK

¹Helsinki University Hospital, Clinic of Gastroenterology, Helsinki, Finland, ²Esior Oy, Kuopio, Finland, ³Helsinki University Hospital/Jorvi Hospital, Department of Gastroenterology, Espoo, Finland, ⁴Kuopio University Hospital, Department of Internal Medicine, Kuopio, Finland, ⁵South Karelia Central Hospital, Department of Internal Medicine, Lappeenranta, Finland, ⁶Lapland Central Hospital, Department of Internal Medicine, Rovaniemi, Finland, ⁷Central Hospital of Central Finland, Department of Internal Medicine, Jyväskylä, Finland, ⁸Satakunta Central Hospital, Department of Internal Medicine, Pori, Finland, ⁹Vaasa Central Hospital, Department of Internal Medicine, Vaasa, Finland, ¹⁰Turku University Hospital, Division of Gastroenterology, Department of Medicine, Turku, Finland, ¹¹Kainuu Central Hospital, Department of Internal Medicine, Kajaani, Finland, ¹²Turku University Hospital/Salo hospital, Division of Gastroenterology, Department of Medicine, Salo, Finland, ¹³Central Ostrobothnia Central Hospital, Department of Internal Medicine, Kokkola, Finland, ¹⁴Janssen-Cilag AB, Medical Affairs, Solna, Sweden, ¹⁵Janssen-Cilag Oy, Medical Affairs, Espoo, Finland, ¹⁶Janssen-Cilag Limited, EPC - HEMAR, Buckinghamshire, UK, ¹⁷Department of Internal Medicine, Päijät-Häme Central Hospital, Lahti, Finland

¹IIS Hospital La Fe, Gastroenterology, Valencia, Spain, ²Hospital Universitari i Politècnic La Fe, Gastroenterology, Valencia, Spain, ³CIBEREHD, Madrid, Spain, ⁴IIS Hospital La Fe, Biostatistics, Valencia, Spain