Some properties of the USP content-uniformity test as related to control charts and validation of solid dosage forms

The statistical properties of the USP content-uniformity test have been investigated in detail in other reports. This note shows that control charts for the mean potency of a solid dosage form which are constructed using typical individual content-uniformity assays in conjunction with composite assay(s), show tight limits when the product has a high probability of passing the content-uniformity test. From a practical point of view, this is a strong argument in favor of the test and recommends the test as a quality control tool.