I obtained my medical degree from the University of Leiden in the Netherlands. I trained to be a dermatologist at the Leiden University Medical Centre, where I have remained a staff member in the Dermatology Department since qualifying in 1999. Currently, I head the Allergy Department within the Department of Dermatology, and I am responsible for the training of dermatologists in this context, in addition to caring for patients. From 1999 to 2004 I also worked for the Medicines Evaluation Board as a clinical assessor for dermatology products. I have been Methods Editor for the Cochrane Skin Group from 2012 to 2018.
My expertise lies in allergy and evidence‐based medicine, topics on which I have been extensively published in the 
Cochrane Library and in journals such as the British Journal of Dermatology (BJD), Journal of the American Academy of Dermatology, JAMA Dermatology, JAMA, New England Journal of Medicine, Contact Dermatitis and Allergy. Furthermore, I am a Recommendation Editor for DynaMed since 2014 and I am member of 
the GRADE working group since 2012. I have written many systematic reviews and updates for the treatment of 
rosacea, female pattern hair loss, eczema, urticaria, hirsutism and fungal infections, and also in other fields. In 
addition, I am involved in the development Dutch dermatology guidelines