Food analytical methods are classified as either continuous or categorical based on their response type. When a qualitative method is proposed as a standard assay, it must be validated to demonstrate its suitability for the intended purpose. This validation process depends on the availability of standard reference materials or an established reference method. While international standards provide guidance for this process, misinterpretations of performance characteristics—such as the limit of detection, level of detection, relative limit of detection, and probability of detection, in combination with statistical models ranging from the normal and Poisson distributions to the beta-binomial distribution and beyond —have led to inconsistencies. Adding to this complexity, different validation standards use different validation criteria. As a result, there is a growing need for harmonization to ensure comparability across methods. In this context, the potential application of Bayesian methods also arises. The potential of a Bayesian approach for a practical equivalence procedure has never been developed to provide an equivalence estimate in cases where results from similar matrices are compared. This Workshop will review the goals of categorical testing, current standard methods for validation and determining equivalence and the possibilities for potentially harmonizing or interchanging results from them.