1. Department of Dermatology; Eberhard Karls University; Liebermeisterstrasse 25; Tübingen; D-72076; Germany
2. Department of Dermatology; Ludwig Maximilians University; Munich; Germany
3. Department of Dermatology; University of Ulm; Ulm; Germany
4. Department of Dermatology; University of Zürich; Zürich; Switzerland
5. Department of Medical Biometry; Eberhard Karls University; Liebermeisterstrasse 25; Tübingen; D-72076; Germany
6. Clinic of Dermatology; Immenstadt; Germany
7. Department of Dermatology and Allergy Biederstein; Technische Universität München; Munich; Germany