1. Department of Gastroenterology, University Hospital Zurich [USZ] and University of Zurich, Zurich, Switzerland
2. Institute of Social and Preventive Medicine [IUMSP], Lausanne University Hospital, Lausanne, Switzerland
3. Center of Gastroenterology, Clinic Hirslanden, Zurich, Switzerland
4. Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland
5. Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois [CHUV] and University of Lausanne, Lausanne, Switzerland
6. Center of Gastroenterology and Hepatology, Zurich, Switzerland