Key to sound validation studies is the formalization and harmonization of procedures for design of experiment and interpretation of results. International guidelines (ISO 5725, ENGL) are available for the validation of GMO detection methods, and ad-hoc validation statistics (e.g. per cent bias, repeatability and reproducibility) are used for in-house and inter-laboratory testing and decision-making. Acceptability criteria have been set but not every situation can be covered by a preset rule; the interpretation of results in validation largely depends on expert judgement being a matter of professional judgment and expertise. Fuzzy logic-based techniques may be used to summarize the information obtained by independent validation statistics and are helpful in such respect. A comprehensive indicator of method performance permits direct comparison between methods and facilitates the evaluation of multiple, yet contradictory statistics. The European Union Reference Laboratory for GM Food and Feed has already proposed the fuzzy principle in the context of method validation. Other studies have also proved its applicability in other areas of GMO analysis, but the application has been limited hitherto. In this article, we review the fuzzy logic principle and its potential to support the continuous progress of GMO science and routine laboratory analyses.
