1. Department of General, Visceral, Thoracic and Vascular Surgery, University Hospital Ruppin-Brandenburg, 16816 Neuruppin, Germany
2. Brandenburg Medical School Theodor Fontane (MHB), 16816 Neuruppin, Germany
3. Faculty of Health Sciences Brandenburg (FGW), University Hospital Ruppin-Brandenburg (UKRB), Fehrbelliner Straße 38, 16816 Neuruppin, Germany
4. Centre for Health Services Research Brandenburg (ZVF-BB), 15562 Rüdersdorf, Germany
5. Department of Psychosomatics, 16816 Neuruppin, Germany
6. Medical Clinic B, 16816 Neuruppin, Germany
7. Division of Medicine, Department of Gastroenterology, Metabolism and Oncology, University Hospital Ruppin-Brandenburg, Brandenburg Medical School, 16816 Neuruppin, Germany