1. Competence Network IBD , Kiel , Germany
2. Interdisciplinary Crohn Colitis Centre , Minden , Germany
3. Clinic of General Internal Medicine I, University Hospital Schleswig-Holstein , Campus Kiel, Kiel , Germany
4. Gastroenterology Practice , Minden , Germany
5. Center for Gastroenterology Saar MVZ , Saarbruecken , Germany
6. Gastroenterology Practice , Iserlohn , Germany
7. Gastroenterology Practice , Kassel , Germany
8. Gastroenterology Practice at Germania-Campus , Muenster , Germany
9. III. Medical Clinic, University Hospital of Augsburg , Augsburg , Germany
10. Medical Clinic 1, Friedrich-Alexander-University Erlangen-Nürnberg , Erlangen , Germany
11. Gastroenterology Practice Leipzig , Leipzig , Germany
12. Gastroenterology Practice , Bremen , Germany
13. Gastroenterology Practice , Heidelberg , Germany