1. Department of Dermatology; Venereology; and Allergology; HELIOS St. Elisabeth Hospital Oberhausen; Oberhausen Germany
2. Department of Dermatology and Venereology; University Hospital Cologne; Cologne Germany
3. Department of Dermatology; Venereology; and Allergology; Charité - University Medical Center Berlin; Berlin Germany
4. Department of Dermatology and Allergology; University Hospital Bonn; Bonn Germany
5. Interdisciplinary Center for Clinical Studies (IZKS); University Medical Center Mainz; Mainz Germany
6. Department of Dermatology and Venereology; University Hospital Graz; Graz Austria
7. Department of Dermatology and Allergology; University Hospital Ulm; Ulm Germany
8. Department of General Pediatrics; Asklepios Hospital; St. Augustin Germany
9. Emma Reil; Scleroderma Support Group; Heilbronn Germany
10. Department of Dermatology; Venereology; und Allergology; University Hospital Frankfurt and Work Group EbM Frankfurt; Institute for General Medicine; Johann Wolfgang Goethe University Frankfurt; Frankfurt am Main Germany