1. Department of Gastroenterology and Hepatology, 2nd Propedeutic Department of Internal Medicine, Medical School, Aristotle University, 54124 Thessaloniki, Greece
2. Department of Gastroenterology, Alexandra General Hospital, 11528 Athens, Greece
3. Department of Gastroenterology, Venizeleio General Hospital, 71409 Heraklion, Greece
4. Department of Gastroenterology, General Hospital of Nikaia-Piraeus “Agios Panteleimon”, General Hospital Ditikis Attikis “Agia Varvara”, 12351 Athens, Greece
5. Department of Gastroenterology, GHA ‘Evaggelismos—Polykliniki’, 10676 Athens, Greece
6. Department of Gastroenterology, Theagenio Anticancer Hospital of Thessaloniki, 54639 Thessaloniki, Greece
7. Department of Gastroenterology and Hepatology, 424 Military General Hospital, 54124 Thessaloniki, Greece
8. GI-Unit, Department of Internal Medicine, University Hospital of Patras, 26504 Patras, Greece
9. Department of Gastroenterology, Tzaneion General Hospital, 18536 Piraeus, Greece
10. Department of Gastroenterology, Medical School of National and Kapodistrian University of Athens, General Hospital of Athens “Laiko”, 11527 Athina, Greece
11. Department of Gastroenterology, University Hospital of Ioannina Medical School, 45500 Ioannina, Greece
12. Department of Gastroenterology, Metaxa Memorial General Hospital, 18537 Piraeus, Greece
13. Gastroenterology and Hepatology Division of the First Propedeutic Department of Internal Medicine, AHEPA University Hospital, 54636 Thessaloniki, Greece
14. Gastroenterology-Liver Unit, Second Department of Internal Medicine, Hippokratio General Hospital, National and Kapodistrian University of Athens, 54643 Athens, Greece
15. GI-Unit, 3rd Academic Department of Internal Medicine, Sotiria Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece
16. Department of Surgery, Aretaieion University Hospital, 11528 Athens, Greece
17. Department of Gastroenterology, University Hospital of Heraklion, 71500 Heraklion, Greece
18. Department of Gastroenterology, General Hospital of Chania “Agios Georgios”, 73300 Chania, Greece
19. Laboratory of Hygiene, Social—Preventive Medicine and Medical Statistics, Faculty of Medicine, School of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
20. Department of Gastroenterology, “Konstantopoulio-Patission” General Hospital, 14233 Nea Ionia, Greece