Wayne, Pennsylvania, USA—September 2013—The Clinical and Laboratory Standards Institute (CLSI) has published an updated version of EP09-A3—Measurement Procedure Comparison and Bias Estimation Using Patient Samples; Approved Guideline—Third Edition. This document provides guidance for one of the most common techniques used by both manufacturers and clinical laboratories to estimate the bias of an in vitro diagnostic measurement procedure relative to a comparator.
This edition of the document addresses the design of measurement procedure comparisons using patient samples and subsequent data analysis techniques used to determine the bias between two in vitro diagnostic measurement procedures. Updates to this latest version of EP09 provide more reasons for comparisons based on patient samples; regression descriptions including weighted options, Deming, and Passing-Bablok techniques; measurement of bias at clinical decision points; and outlier detection using extreme studentized deviate.
Jeffrey R. Budd, PhD, EP09-A3 document Chairholder, of Beckman Coulter, Chaska, Minnesota, USA, emphasized, “the practical nature of this guideline—̲there are almost no equations outside of the appendixes, and the concepts are almost always portrayed visually, as well as in written text.” Budd stated: “The document was written with the goal of meeting the needs of all users, from the beginning lab tech to the advanced research scientist.”
EP09-A3 describes a stepwise approach to comparing measurement procedures that can be used by manufacturers of in vitro diagnostic reagents, which includes those who create laboratory-developed tests, as well as regulatory bodies and clinical laboratory personnel.
CLSI is a not-for-profit membership organization that brings together the varied perspectives and expertise of the worldwide laboratory community for the advancement of a common cause: to foster excellence in laboratory medicine by developing and implementing clinical laboratory standards and guidelines that help laboratories fulfill their responsibilities with efficiency, effectiveness, and global applicability. For additional information, visit the CLSI website at www.clsi.org or call 610.688.0100.