Specifies guidance for laboratories on the evaluation of a new reagent lot, including a protocol using patient samples to detect significant changes from the current lot.

This guideline provides a simple, practical, and statistically sound protocol to evaluate the consistency of patient sample results when a new analytical reagent lot replaces a reagent lot currently in use. This document is designed primarily for use with quantitative measurement procedures, but the same principles can be applied to measurement procedures that provide a clinically qualitative result based on a supplied quantitative measurement. This guideline is not intended for use with measurement procedures that only provide qualitative results. This guideline is intended for use in the clinical laboratory and is designed to work within the practical limitations that exist in that environment. This guideline is not intended to provide detailed procedures for reagent manufacturers. The needs of reagent lot-to-lot testing by manufacturers, and the resources available, are different from those of the clinical laboratory. However, reagent manufacturers may use this document to understand the types of verification studies that may be performed in their customers’ laboratories.