1. Department of Gastroenterology, University Hospital Giessen and Marburg , Marburg , Germany
2. Department of General and Visceral Surgery, St. Josefs-Hospital , Wiesbaden , Germany
3. Department of Gastroenterology, DKD Helios Klinik Wiesbaden , Wiesbaden , Germany
4. Institute of Medical Biostatistics , Epidemiology and Informatics (IMBEI), Division Biostatistics and Bioinformatics, , Mainz , Germany
5. University Medical Center Johannes Gutenberg University , Epidemiology and Informatics (IMBEI), Division Biostatistics and Bioinformatics, , Mainz , Germany
6. Department of Visceral , Transplant, Thoracic and Vascular Surgery, , Leipzig , Germany
7. University Medical Center of Leipzig , Transplant, Thoracic and Vascular Surgery, , Leipzig , Germany