1. German Center for Health Services Research in Dermatology (CVderm); Institute for Health Services Research in Dermatology and Nursing (IVDP), University Medical Center Hamburg-Eppendorf (UKE); Hamburg, Germany
2. Department of Vascular Medicine; University Medical Center Hamburg-Eppendorf (UKE); Hamburg Germany
3. University Hospital of Giessen and Marburg; Marburg Germany