1. Ear, Nose, and Throat Unit, Villa Montallegro Private Clinic, Genoa, Italy
2. Pneumologic and Allergological Paediatric Unit, Istituto G. Gaslini, Genoa, Italy
3. Department of Health Sciences, Section of Biostatistics, Genoa University, Genoa, Italy
4. Allergy and Respiratory Diseases Clinic, Istituto Di Ricovero e Cura a Carattere Scientifico–University Hospital San Martino, Genoa, Italy