1. Internistische Gemeinschaftspraxis für Verdauungs-und Stoffwechselkrankheiten, Leipzig, Germany
2. Medical Faculty, Friedrich Schiller University Jena, Jena, Germany
3. Zentrum für Gastroenterologie Saar MVZ GmbH, Saarbrücken, Germany
4. Department of Internal Medicine III, Division of Gastroenterology and Hepatology, Medical University of Vienna, Vienna, Austria
5. Department of Gastroenterology and Hepatology, University Hospital Heidelberg, Heidelberg, Germany
6. Department of Internal Medicine I, Martin-Luther-University of Halle-Wittenberg, Halle, Germany
7. Gastroenterologische Gemeinschaftspraxis Herne, Herne, Germany
8. Department of Medicine 1, University of Erlangen-Nürnberg, Erlangen
9. Medical Faculty, University of Cologne, Köln, Germany
10. Medizinische Klinik und Poliklinik B, Universitätsklinikum Münster, Münster, Germany
11. Klinik am See, Rüdersdorf b. Berlin, Germany
12. Department for Internal and Integrative Medicine, University of Duisburg-Essen, Duisburg, Germany
13. Kompetenznetz Darmerkrankungen e.V, Kiel, Germany
14. Medical Department III, University Hospital RWTH Aachen, Aachen, Germany
15. Department of Internal Medicine IV, Jena University Hospital, Jena, Germany