1. Specialty School of Paediatrics, Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy
2. Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy
3. Pediatric Emergency Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
4. Gastroenterology and Digestive Endoscopy Unit, Forlì-Cesena Hospitals, AUSL Romagna, 47121 Forlì, Italy
5. Pediatric Intermediate Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via della Commenda 9, 20122 Milan, Italy
6. Department of Medical and Surgical Sciences for Mothers, Children and Adults, University of Modena and Reggio Emilia, 41125 Modena, Italy
7. Pediatric Unit, Carpi Hospital, 41012 Carpi, Italy
8. Department of Pediatrics, AUSL, Guglielmo da Saliceto Hospital, 29121 Piacenza, Italy
9. Department of Paediatrics, Santa Maria delle Croci Hospital, AUSL della Romagna, 48121 Ravenna, Italy
10. Pediatric Clinic, Rimini Hospital, AUSL Romagna, 47923 Rimini, Italy
11. Institute for Maternal and Child Health, IRCCS “Burlo Garofolo” and University of Trieste, 34137 Trieste, Italy
12. Pediatric Unit, AUSL Bologna, Ospedale Maggiore, 40133 Bologna, Italy
13. Pediatrics Unit, Santa Maria Nuova Hospital, Azienda Unità Sanitaria Locale (AUSL)-Scientific Institute for Research and Healthcare (IRCCS) of Reggio Emilia, 42123 Reggio Emilia, Italy
14. Pediatrics Unit, G.B. Morgagni-L. Pierantoni Hospital, Azienda Unità Sanitaria Locale (AUSL) Romagna, 47121 Forlì, Italy
15. Gastro-Esophageal Organic Disease Unit, IRRCS Azienda Universitaria-Ospedaliera di Bologna, 40138 Bologna, Italy