1. Department of Gastroenterology and Metabolism Poznan University of Medical Sciences Poznan Poland
2. 4th Department of Pediatrics Aristotle University Thessaloniki Greece
3. Klinik und Poliklinik für Kinder‐ und Jugendmedizin des Universitätsklinikums Dresden Germany
4. University Children's Clinic Tübingen Germany
5. Department of Pediatric Gastroenterology Erasmus MC‐Sophia Rotterdam The Netherlands
6. Department of Child Health University of Wales Swansea Singleton Hospital Swansea United Kingdom