1. Institute for Health Services Research in Dermatology and Nursing (IVDP); University Medical Center Hamburg-Eppendorf (UKE); Hamburg Germany
2. Department of Dermatology; Jena University Hospital; Jena Germany
3. Dermatology Practice Mönchengladbach; Mönchengladbach Germany
4. Department of Dermatology; Heidelberg University Hospital; Heidelberg Germany
5. Tibarg Dermatology Group Practice; Hamburg Germany
6. Clinic for Dermatology, Venereology and Allergology; Frankfurt University; Frankfurt am Main Germany