[Statistical considerations for weight variation and content uniformity tests].

Weight variation and content uniformity tests are both intended to ensure the uniformity of dosage units. In the Japanese Pharmacopoeia, modifications to these tests have been proposed in thirteenth revision with new concepts based on statistical considerations. The points of change are as follows: 1. introduction of a variables requirement, 2. matching of sampling plans of weight variation and content uniformity tests, 3. clarification of conditions for application of content uniformity tests, 4. criterion of quality based on deviation not from the sample mean but from the label claim.