1. Dermatology Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester Academic Health Science Centre NIHR Manchester Biomedical Research Centre Manchester M13 9PT U.K
2. Centre for Pharmacoepidemiology and Drug Safety School of Health Sciences The University of Manchester Manchester M13 9PT U.K
3. IVDP – Institute for Health Services Research in Dermatology and Nursing University Medical Center Hamburg‐Eppendorf Hamburg Germany
4. Arthritis Research U.K. Epidemiology Unit The University of Manchester Manchester M13 9PT U.K