1. Erasmus Medical Center; Department of General Practice; PO Box 2040 Room Ff303 Rotterdam Netherlands 3000 CA
2. Erasmus MC - Sophia Children's Hospital; Department of Paediatrics, Paediatric Rheumatology; PO Box 2060 Rotterdam Netherlands 3000 CB
3. University of Wales College of Medicine; Department of Dermatology; Cardiff Wales UK
4. University of Oxford; Nuffield Department of Primary Care Health Sciences; Woodstock Road Oxford UK OX2 6GG
5. University Medical Centre Groningen; Department of General Practice; Groningen Netherlands