[1] Dutch Skin Fdn, Dept Dermatol, Utrecht, Netherlands
[2] Dutch Skin Fdn, Dept Dermatol, Utrecht, Netherlands
[3] Univ Amsterdam, Acad Med Ctr, Dept Clin Epidemiol Biostat & Bioinformat, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[4] Vrije Univ Amsterdam, Med Ctr, Dept Dermatol, Amsterdam, Netherlands
[5] Vrije Univ Amsterdam, Med Ctr, Dept Epidemiol & Biostat, Amsterdam, Netherlands