Tree nut allergies
We included 18 studies on accuracy of diagnostic tests for tree nut allergy. Seven studies for SPT [48, 50, 63, 70, 114, 123, 148, 156], 8 for sIgE [44, 48, 50, 63, 70, 87, 122, 123, 148, 156] and 8 for CRD met inclusion criteria for hazelnut allergy meta-analyses [44, 47, 48, 50, 63, 66, 70, 87, 122, 123, 148]. SPT to hazelnut and sIgE to hazelnut showed pooled sensitivities of 82% and 79% and pooled specificities of 78% and 62%, respectively (Table 2 ). The specificity increased to 73% in the 2–16-year age group for sIgE-to hazelnut (Table 6 ). Cor a 14-sIgE [44, 47, 48, 50, 63, 66, 70, 122, 123, 148] showed pooled sensitivity of 73% and high specificity of 95% at the 0.64 kUA/L cut-off. For the 2–16-year age group Cor a 14 maintains high specificity of 97%.