1. Department of Dermatology and Allergy; Charité - Universitätsmedizin Berlin; Berlin Germany
2. Allergy Vigilance Network; Vandoeuvre Les Nancy; Nancy France
3. Allergy Unit; Department of Dermatology; University Hospital Basel; Basel Switzerland
4. Department of Dermatology; Paracelsus Medizinische Privatuniversität Salzburg; Salzburg Austria
5. Allergy Department; Hospital Clinico San Carlos IdISSC; Madrid Spain
6. Allergy Section; Department of Internal Medicine; Hospital Vall d′Hebron; Barcelona Spain
7. Department of Clinical Immunology and Allergy; University of Lodz; Lodz Poland
8. Department of Clinical Immunology; Wroclaw Medical University; Wroclaw Poland
9. ALL-MED Medical Research Institute; Wroclaw Poland
10. Clinical Allergology Department; Pomeranian Medical University Szczecin; Szczecin Poland
11. Centre for Paediatrics and Child Health; Institute of Human Development; University of Manchester; Manchester UK
12. Allergy Department; 2nd Paediatric Clinic; University of Athens; Athens Greece
13. Department of Paediatric Pneumology and Immunology; Charité - Universitätsmedizin Berlin; Berlin Germany
14. Allergology, Paediatrics; University Hospital Alexandrovska Sofia; Sofia Bulgaria
15. Allergy Outpatient Clinic; Tokuda Medical Centre Sofia; Sofia Bulgaria
16. Allergy Unit; Department of Internal Medicine; University Hospital Ospedali Riuniti; Ancona Italy
17. Department of Mother and Child Health; Padua General University Hospital; Padua Italy
18. Paediatrics and Child Health; University College Cork; Cork Ireland
19. Institute for Social Medicine, Epidemiology and Health Economics; Charité - Universitätsmedizin Berlin; Berlin Germany