1. Leeds Teaching Hospitals NHS Trust Leeds UK
2. Clinic of Dermatology, University Hospital and Faculty of Medicine University of Coimbra Coimbra Portugal
3. University Hospital Antwerp (UZA) and University of Antwerp (UA) Antwerp Belgium
4. Alfa Medical Services Bucharest Romania
5. Dermato‐Aesthetic Institute Dr. Irinel Nedelcu Bucharest Romania
6. Department of Dermatology, Venereology and Allergology St. Josef Hospital, University Medical Centre, Ruhr University Bochum Bochum Germany
7. Clinica Dermatologica—DISSAL—Università di Genova Ospedale Policlinico San Martino Genova Italy
8. Allergy Section, Marina Baixa Hospital Villajoyosa Spain
9. Department of Dermatology, Hospital del Mar, IMIM Universitat Pompeu Fabra Barcelona Spain
10. Contact Dermatitis Institute Phoenix Arizona USA
11. Servicio de Dermatología, Complejo Hospitalario de Navarra Pamplona Navarra Spain
12. Department of Occupational and Environmental Dermatology Lund University, Skane University Hospital Malmö Sweden
13. National Allergy Research Centre, Department of Dermatology and Allergy Copenhagen University Hospital Herlev‐Gentofte Hellerup Denmark
14. Paul‐Ehrlich‐Institut Langen Germany
15. Chemotechnique Diagnostics Vellinge Sweden
16. IRCCS Galeazzi Orthopaedic Institute, Milan Department of Biomedical, Surgical and Dental Sciences University of Milan Milan Italy
17. Department of Dermatology–Venerology and Dermato‐oncology Semmelweis University Budapest Hungary
18. VU University Amsterdam Netherlands
19. University of Groningen, University Medical Center Groningen Groningen Netherlands
20. Jagiellonian University Medical College Krakow Poland
21. Dermatology Section, Department of Medicine and Surgery University of Perugia Perugia Italy
22. Bispebjerg Hospital University of Copenhagen Copenhagen Denmark
23. Department of Medical Informatics, Biometry and Epidemiology University of Erlangen‐Nürnberg Erlangen Germany