1. Division of Pediatric Respiratory MedicineHospital Universitario DonostiaSan Sebastián Spain
2. Department of PediatricsUniversity of the Basque Country (UPV/EHU)San Sebastián Spain
3. Pediatric Allergy, Pulmonary and Cystic Fibrosis SectionHospital Universitari Vall d'HebronBarcelona Spain
4. Departament of Pediatrics, Obstetrics, Gynecology, Preventive Medicine and Public HealthUniversitat Autònoma de BarcelonaBarcelona Spain
5. Pathology and Laboratory MedicineChildren's Hospitals and Clinics of MinnesotaMinneapolis‐St. Paul Minnesota
6. Department of PediatricsUniversity of Colorado School of MedicineColorado
7. Pathology DepartmentHospital Universitari Vall d'HebronBarcelona Spain
8. Pediatric Radiology DepartmentHospital Universitari Vall d'HebronBarcelona Spain
9. Department of PediatricsHospital Marqués de ValdecillasSantander Spain
10. Department of PediatricsHospital de OurenseOurense Spain
11. Growth and Development Research UnitVall d'Hebron Research Institute (VHIR)Barcelona Spain
12. Center for Biomedical Research on Rare Diseases (CIBERER)Instituto de Salud Carlos III Spain
13. Department of PediatricsHospital Universitari Vall d'HebronBarcelona Spain
14. Biomedical Research Centre Network for Respiratory Diseases (CIBERES)San Sebastián Spain