1. Department of Pediatrics, Institute of Child Health IRCCS Burlo Garofolo, Trieste, Italy
2. Unit of Epidemiology and Biostatistics, Institute of Child Health IRCCS Burlo Garofolo, Trieste, Italy
3. Unit for Health Services Research and International Health, Institute of Child Health IRCCS Burlo Garofolo, Trieste, Italy
4. Department of Pediatrics, “S. Maria degli Angeli” Hospital, Pordenone, Italy