1. Division of Gastroenterology and Hepatology, Cantonal Hospital St Gallen, Switzerland
2. Center for Disease Analysis, Lafayette, Colorado, USA
3. Division of Infectious Diseases, Cantonal Hospital St Gallen, Switzerland
4. Arud Centres for Addiction Medicine, Zurich, Switzerland
5. Swiss HPB (Hepato-pancreato-biliary) Centre and Department of Gastroenterology and Hepatology, University Hospital Zurich, Switzerland
6. Divisions of Gastroenterology and Hepatology and of Clinical Pathology, University Hospital of Geneva, Switzerland