Performance criteria for the verification of IgE and tryptase assay methods: recommendations from the AllergoBioNet network

Abstract : Accreditation of an in vitro diagnostic assay according to the NHENI/ISO 15189 standard requires to analyze its technical performance before implementation for routine use, and annually when reviewing effectiveness of quality controls. Performance is evaluated through repeatability, intermediate fidelity, accuracy and uncertainty of measurement. The coefficients of variation (CV) of the infra-assay and inter-assay precision tests must be compared with those of ``peers'' (results from laboratories employing the same method) and also with those obtained with ``all methods'', i.e., results from all laboratories performing the same assay, irrespective of the method. To our best knowledge, there is currently no French or international recommendation on what the acceptable limits of performance for specific IgE and tryptase assays should be. Therefore, the AllergoBioNet network of hospital allergy laboratories set out to characterize the performance of their current methods as a basis for the development of recommendations. The results provided by 24 centers were analyzed and led to consensus recommendations for specific IgE, total and tryptase assays.