1. Department of Rheumatology; Medical University of Łódź; Łódź Poland
2. Department of Respiratory Epidemiology and Public Health; Imperial College; London UK
3. Institute for Social Medicine, Epidemiology and Health Economics; Charité - Universitätsmedizin Berlin; Berlin Germany
4. Upper Airways Research Laboratory; Department of Otorhinolaryngology and Logopaedic-Audiologic Science; Ghent University; Ghent Belgium
5. Institute for Occupational Health of R. Macedonia; University ‘‘Sts Cyril and Methodius’’ Skopje; Skopje Macedonia
6. Department of Epidemiology; Faculty of Medicine; Medical University of Silesia; Katowice Poland
7. Department of Occupational and Environmental Medicine; Odense University Hospital; Odense Denmark
8. Department of Dermatology and Allergy Centre; Odense University Hospital; Odense Denmark
9. Department of Respiratory Medicine; Montpellier University; Montpellier France
10. Oslo University Hospital; Rikshospitalet; Oslo Norway
11. Department of Environmental Medicine; Karolinska Institutet; Stockholm Sweden
12. Unit of Heart and Lung Diseases; Karolinska Institutet; Stockholm Sweden
13. Department of Otorhinolaryngology; Academic Medical Centre; University of Amsterdam; Amsterdam The Netherlands
14. Department of Public Health and Clinical Medicine; Umea University; Umea Sweden
15. Department of Respiratory Medicine; Institute of Biomedicine and Molecular Immunology; Palermo Italy
16. Department of Respiratory Cell and Molecular Biology; University of Southampton; Southampton UK
17. Department of Medical Sciences, Respiratory, Allergy and Sleep Research; Uppsala University; Uppsla Sweden
18. Department of Internal Medicine; Jagiellonian University Krakow; Krakow Poland
19. Environmental Health Research Institute; Heinrich Heine University; Dusseldorf Germany
20. Department of Dermatology and Allergy; Technical University Munich; Munich Germany
21. Department of Immunology and Allergology; University Hospital Coimbra; Coimbra Portugal
22. Krefting Research Centre; University of Gothenburg; Gothenburg Sweden
23. Allergy Department; 2nd Paediatric Clinic; University of Athens; Athens Greece
24. Department of Otorhinolaryngology and Finnish Institute of Occupational Health; Helsinki University Hospital; Helsinki Finland
25. Center for Applied Genomics; The Children's Hospital of Philadelphia; Philadelphia PA USA
26. Department of Dermatology and Allergy; Charite′- Universitahtsmedizin Berlin; Berlin Germany
27. Department of Immunology, Rheumatology and Allergy; Medical University of Łódź; Łódź Poland