BAT Cow's Milk for the Replacement of the Food Challenge Test

The prevalence of children suspected of a cow's milk allergy is 17% in the Netherlands. Cow's milk diagnosis is based on a food challenge test However, this food challenge test is expensive, time consuming, risky, with waiting lists of several months. This waiting time results in unnecessarily long-term use of expensive hypoallergenic milk formula Therefore, there is a great need to introduce a better and faster diagnostic test for cow's milk allergy diagnosis in standard care. The in vitro Basophil Activation Test (BAT) is cheap, quick (result \< 1 day, no waiting list), safe for the child and is a reliable alternative for the food challenge test to diagnose an IgE-mediated allergy. A diagnostic work-up with the BAT is expected to achieve a relevant reduction in the number of expensive and risky food challenges and the prescription of hypoallergenic formula. The reduction in diagnostic delay will increase quality of life. Objective: Determination of the (cost)effectiveness of the replacement of the expensive, risky and time-consuming food challenge test by the Basophil Activation Test (BAT) for the diagnosis of an IgE-mediated cow's milk allergy in children.