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. Kompetenzzentrum Chronischer PruritusUniversitätsklinikum Münster (UKM) Münster Germany
3. LEO Pharma GmbH Neu‐Isenburg Germany