1. Division of Gastroenterology of the University of Verona, Azienda Ospedaliera Universitaria Integrata di Verona, Verona, Italy; and Division of Gastroenterology and Hepatology & UNC Center for Functional GI and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
2. Department of Clinical Medicine and Surgery, ‘Federico II’ University of Naples, Naples, Italy
3. Division of Gastroenterology, University of Padua, Azienda Ospedaliera di Padova, Padua, Italy