CLSI EP15 User Verification of Precision and Estimation of Bias This document provides a protocol for estimating imprecision and bias in clinical laboratory quantitative measurement procedures. The protocol can be completed in as few as five days.

Calculate SE RM for scenario A when “standard error” or “standard uncertainty” (abbreviated by lowercase “u”) or “combined standard uncertainty” (often denoted by “uC ”)

CLSI’s StatisPro2 software provides a complete, user-friendly implementation of the EP15 data analysis, but this can also be handled by combining readily available ANOVA software with table look-ups and simple spreadsheet calculations.

Calculate SE RM for scenario A when “standard error” or “standard uncertainty” (abbreviated by lowercase “u”) or “combined standard uncertainty” (often denoted by “uC ”)

Run this analysis with our CLSI EP15 Verification Calculator. CLSI EP15-A3 is the user verification protocol for quantitative measurement procedures in clinical and reference laboratories.

Calculate SE RM for scenario A when “standard error” or “standard uncertainty” (abbreviated by lowercase “u”) or “combined standard uncertainty” (often denoted by “uC ”)

Calculation of the verification interval would be complicated, but the committee simplified it greatly by providing tables for the difficult-to-calculate quantities based on the number of replicate measurements per run, the number of runs, and the uncertainty of the target value.

Both Excel files automatically calculate repeatability and within-laboratory (total) precision and determine method acceptability using Upper Verification Limits (UVL) derived from chi-square statistics at 95% confidence, with appropriate adjustment for the number of control levels tested.

CLSI EP15-A3 provides guidance on the user verification of precision and the estimation of bias for laboratory test methods. It outlines the steps and procedures that clinical laboratories should follow to evaluate the performance of a test method they intend to implement.

CLSI EP15IG User Verification of Precision Implementation Guide This implementation guide outlines the minimum procedures necessary for a medical laboratory to verify precision claims made by manufacturers or for laboratory-developed tests.