scope:

This document provides guidance for designing an experiment and selecting methods to quantify systematic measurement error (bias or difference) between measurement procedures based on comparing patient samples. It provides procedures to determine the average bias between two measurement procedures either across their measuring intervals or at selected concentrations. Intended users of this guideline are manufacturers of in vitro diagnostic (IVD) reagents-which includes those who create laboratory-developed tests-as well as regulatory bodies and clinical laboratory personnel.

This document is for use with measurement procedures that provide quantitative numerical results. This document is not intended for use with ordinal IVD measurement procedures, commonly referred to as qualitative procedures (see CLSI document EP12¹). This document is not intended to address evaluation of random error (see CLSI documents EP05² and EP15³) or to determine the total error inherent in a comparison of measurement procedures (see CLSI document EP21⁴). It is not intended to measure the variability of multiple replicates collected during the measurement of a sample, nor is it intended to measure the bias of individual measurements such as those resulting from sample interference (as covered in CLSI document EP07⁵).