1. Department of Otorhinolaryngology, Head and Neck Surgery University of Tübingen Tübingen Germany
2. Karl Landsteiner University Krems Austria
3. Vienna Challenge Chamber Power Project GmbH Vienna Austria
4. Hospital Infanta Leonor Madrid Spain
5. Allergy and Clinical Immunology Unit Azienda Usl Toscana Centro, Ospedale San Giovanni di Dio Florence Italy
6. Department of Clinical Immunology and Allergy Frimley Park Hospital Frimley UK
7. Royal Surrey County Hospital Guildford UK
8. ClinCompetence Cologne GmbH Cologne Germany
9. Dermatology Department, Division of Allergy University Hospital Basel Basel Switzerland
10. Institute of Medical Statistics and Computational Biology, Faculty of Medicine University of Cologne Cologne Germany