1. Gastroenterology Unit Department of Translational Research and New Technologies in Medicine and Surgery University of Pisa Pisa Italy
2. Division of Gastroenterology Department of Surgery, Oncology and Gastroenterology University of Padova Padova Italy
3. Unit of Biostatistics, Epidemiology and Public Health Department of Cardiac, Thoracic, Vascular Sciences and Public Health University of Padova Padova Italy
4. Department of Medical Science University of Ferrara Ferrara Italy
5. Department of Biomedical Sciences, Humanitas University Via Rita Levi Montalcini 4 20072 Pieve Emanuele, Milan Italy
6. IRCCS Humanitas Research Hospital via Manzoni 56 20089 Rozzano, Milan Italy
7. University of Kansas School of Medicine and VA Medical Center Kansas City Missouri USA