Like any other analytical test, a dissolution test must also be repeatable and reproducible, with a reasonable/acceptable variability as reflected by RSD (or CV) values, say within 5 to 10%. This acceptable variability should be based on a reference product (e.g., PVT) obtained from a multi-lab evaluation.
It has been shown from experimental studies and computer simulation models that such a desired variability is not possible to obtain using the current apparatuses, in particular paddle/basket. In addition, recent discussions of the unexplained high failure rate of PVT are also a reflection of high variability in testing. Therefore, in general, it is not possible to rely on such a highly variable method to establish consistency of the product quality.