1. Department of Pediatric Pneumology, Allergy and Neonatology; Hannover Medical School; Hannover; Germany
2. Research Unit of Molecular Epidemiology; Helmholtz Zentrum Munich; Neuherberg; Germany
3. University Children's Hospital; Technical University Dresden; Dresden; Germany
4. Research Institute for the Prevention of Allergic Diseases; Children's Department; Marien-Hospital; Wesel; Germany
5. Department of Experimental Pneumology; Ruhr-University; Bochum; Germany
6. University Children's Hospital; Albert Ludwigs University; Freiburg; Germany
7. Kinder- und Jugendarztpraxis Laub; Rosenheim; Germany
8. University Children's Hospital; University of Cologne; Cologne; Germany
9. Children's Department; University Teaching Hospital; Landeskrankenhaus Feldkirch; Feldkirch; Austria
10. University Children's Hospital Vienna; Vienna; Austria
11. Institute of Epidemiology and Medical Biometry; Ulm University; Ulm; Germany