1. Department of Respiratory Diseases, Research Center on Asthma and COPD, University of Ferrara, Ferrara, Italy
2. Medical Department, Chiesi Farmaceutici, Parma, Italy
3. Department of Pediatrics, Unit of Allergy and Respiratory Medicine, University of Padova, Padova, Italy
4. Department of Pediatrics, University of Verona, Verona, Italy
5. Respiratory Unit, Department of Pediatrics, Ospedale Pediatrico Bambino Gesù, Rome, Italy
6. Department of Pediatrics, Ospedale Gaslini, Genova, Italy
7. Department of Respiratory Diseases, University of Modena and Reggio Emilia, Modena, Italy