1. Department of Dermatology; Academic Medical Centre; University of Amsterdam; Amsterdam The Netherlands
2. Department of Epidemiology and Biostatistics; EMGO+ Institute for Health and Care Research; VU University Medical Centre; Amsterdam The Netherlands
3. Centre of Evidence Based Dermatology; University of Nottingham; Nottingham UK
4. Division of Dermatology; University Health Network; Toronto ON Canada
5. Department of Dermatology; Brown University; Providence RI USA
6. Department of Dermatology; Institution for Clinical Science; Lund University; Malmö Sweden
7. Medical Library; Academic Medical Centre; Amsterdam The Netherlands
8. Department of Dermatology; Peking University People's Hospital; Peking China
9. Medical Sociology; Institute of Epidemiology and Preventive Medicine; University of Regensburg; Regensburg Germany