Using Tolerance Intervals for Evaluation of Uniformity of Dosage Units Data in Routine Batch Release

Published on: 
Pharmaceutical Technology, Pharmaceutical Technology, February 2024, Volume 48, Issue 2
Pages: 24-29

This article introduces that the basic technique for tolerance interval is implemented using the conventional range 85–115% LC where the proposed range in the PF is not taken into account.


Submitted: June 19, 2023

Accepted: August 29, 2023



The underlying concept for acceptance value (AV) in <905> Uniformity of Dosage Units (UDU) is based on that of tolerance interval (TI). Its maximum allowed acceptance value (L1) is declared not more than (NMT) 15; therefore, meeting the limit will just imply that the lower the value the higher the degree of quality conformance. Due to the formula for L1 or AV (i.e., , the condition foris not justified, and so, compromising that, the AV results will easily pass the limit of NMT 15 most of the time. If recognized by United States Pharmacopeia, such a compromization will continue for official use in a new proposal on “Batch Release Testing for Ensuring Compliance with Uniformity of Dosage Units”.

One of the solutions for such a compromization issue is to simply implement the TI technique to demonstrate that at least 95% or more of the dosage units in routine batches will fall within the range 85–115% of label claim. The technique will provide useful data for batch releasing rather than depending on AV parameter alone.

About the author

Pramote Cholayudth,, is the founder and manager of PM Consult. He is an industrial pharmacist with more than 40 years of experience. He is a guest speaker on process validation to industrial pharmaceutical scientists organized by Thailand’s FDA.

Article details

Pharmaceutical Technology®
Vol. 48, No. 2
February 2024
Pages: 24-29


When referring to this article, please cite it as Cholayudth, P. Using Tolerance Intervals for Evaluation of Uniformity of Dosage Units Data in Routine Batch Release. Pharmaceutical Technology 2024 48 (2).