1. Department of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland
2. Insitute of Social and Preventive Medicine, University Hospital Lausanne – CHUV, Lausanne, Switzerland
3. Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland
4. Division of Gastroenterology and Hepatology, University Hospital Lausanne – CHUV, Lausanne, Switzerland
5. Division of Pediatrics, University Hospital Lausanne – CHUV, Lausanne, Switzerland