1. Department of Gastroenterology, S.Elia - Raimondi Hospital, Caltanissetta, Italy
2. Department of Gastroenterology, St Mark’s Hospital, London, UK
3. Department of Gastroenterology, Hepatology and clinical nutrition, University Hospital Dubrava, University of Zagreb, Zagreb, Yugoslavia
4. Department of Medicine III, University Hospital RWTH Aachen, Germany
5. Department of Internal Medicine, Gastroenterology and Hepatology Unit, Sahlgrenska University Hospital, Gothenburg, Sweden
6. Metabolism and Experimental Therapeutics, Division of Medicine, University College London, London, UK
7. Department of Hepatology and Gastroenterology, Mercy Hospital, Metz, France
8. Gastroenterology department, Hospital de Cascais, Hospital da Luz Setúbal, Portugal
9. Department Gastroenterology & Hepatology AZ Maria-Middelares, Ghent, Belgium
10. Department of Gastroenterology & Hepatology, Amsterdam Gastroenterology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam
11. Digestive Disease Centre, Medical Section, Herlev University Hospital, Copenhagen, Denmark
12. Digestive Disease Center, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy