For quantitative methods, the reproducibility of measurement results is a core performance characteristic. However, in the validation of qualitative methods it is not clear how to characterize a method’s reproducibility.
In a recent article in the Journal of Consumer Protection and Food Safety, QuoData GmbH and the German Federal Office for Consumer Protection (BVL) present a novel approach for determining the reproducibility of qualitative methods.
The approach allows for a better estimation of the reproducibility precision and will be included in the new international standards ISO/FDIS 16140 Part 4 and 5, which defines criteria and procedures for the validation of microbiological methods in the food and feed sector.
To minimize the amount of testing required, efficient orthogonal factorial plans are used.
In interlaboratory method validation studies, this ensures that reliable reproducibility estimates are already possible with data from five participating laboratories.