1. Department of Dermatology and Center for Chronic Pruritus; University Hospital Münster; Münster Germany
2. Moscow Scientific and Practical Center of Dermatovenerology and Cosmetology; Moscow Russia
3. Department of Health, Medical and Neuropsychology; Institute of Psychology; Leiden University; Leiden The Netherlands
4. Institute of Dermatology; Catholic University of the Sacred Heart; Rome Italy
5. Department of Dermatology; University Hospital and Faculty of Medicine; University of Coimbra; Coimbra Portugal
6. Department of Dermatology; Oslo University Hospital; University of Oslo; Oslo Norway
7. Department of Dermatology; University Hospital of Antwerp; Antwerp Belgium
8. Department of Dermatology; Medical University of Graz; Graz Austria
9. Department of Dermatology; Royal Free Hospital; London UK
10. Department of Dermatology and Allergy; Charité - Universitätsmedizin Berlin; Berlin Germany
11. Department of Dermatology; University Hospital of Brest; Brest France
12. Dermatology and Venereology Unit; Department of Medicine; Karolinska University Hospital; Solna Sweden
13. Department of Dermatology; University of Rzeszów; Rzeszów Poland
14. Department of Psychosomatics and Psychotherapy; Münster University Hospital; Münster Germany
15. Dermatological Practice; Bad Bentheim and Department of Dermatology; Klinikum Dortmund GmbH; Dortmund Germany
16. Department of Dermatology; Kantonsspital Aarau; Aarau Switzerland
17. Department of Dermatology, Venereology and Allergology; Wroclaw Medical University; Wroclaw Poland
18. Department of Dermatology and Venereology; Skåne University Hospital SUS Lund; Lund University; Lund Sweden
19. Department of Social Medicine, Occupational and Environmental Dermatology; University of Heidelberg; Heidelberg Germany