1. Academic Medical Center; Department of Dermatology; Meibergdreef 9 Amsterdam Netherlands 1105 AZ
2. Academic Medical Center; Dutch Cochrane Centre; Room J1B - 108 - 2 P.O. Box 22700 Amsterdam Netherlands 1100 DE
3. Radboud University Nijmegen Medical Centre; Department of Dermatology; PO Box 9101 Nijmegen Netherlands 6500 HB
4. Mount Sinai School of Medicine; Department of Dermatology; 5 East 98th Street 5th Floor New York USA 10029