Statistical method for the determination of equivalence of automated test procedures

In the development of test methods for solid dosage forms, manual test procedures for assay and content uniformity often precede the development of automated test procedures. Since the mode of extraction for automated test methods is often slightly different from that of the manual test method, additional validation of an automated test method is usually required. In addition to compliance with validation guidelines, developers of automated test methods are often asked to demonstrate equivalence between the manual and automated test methods. There are problems associated with using the traditional zero-difference hypothesis tests (such as the Student's t-test) for demonstrating equivalence. The use of the Westlake Interval and Schuirmann's Two One-sided test as more rigorous methods of demonstrating equivalence is discussed.