Minimum requirements for the estimation of measurement uncertainty: Recommendations of the joint Working group for uncertainty of measurement of the CSMBLM and CCMB.

Ivana Ćelap,Gordana Juričić,Ines Vukasović,Ana-Maria Šimundić

doi:10.11613/bm.2017.030502

Abstract

The International vocabulary of metrology – Basic and general concepts and associated terms (VIM3, 2.26 measurement uncertainty, JCGM 200:2012) defines uncertainty of measurement as a non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information obtained from performing the measurement. Clinical Laboratory Standards Institute (CLSI) has published a very detailed guideline with a description of sources contributing to measurement uncertainty as well as different approaches for the calculation (Expression of measurement uncertainty in laboratory medicine; Approved Guideline, CLSI C51-A 2012). Many other national and international recommendations and original scientific papers about measurement uncertainty estimation have been published. In Croatia, the estimation of measurement uncertainty is obligatory for accredited medical laboratories. However, since national recommendations are currently not available, each of these laboratories uses a different approach in measurement uncertainty estimation. The main purpose of this document is to describe the minimal requirements for measurement uncertainty estimation. In such way, it will contribute to the harmonization of measurement uncertainty estimation, evaluation and reporting across laboratories in Croatia. This recommendation is issued by the joint Working group for uncertainty of measurement of the Croatian Society for Medical Biochemistry and Laboratory Medicine and Croatian Chamber of Medical Biochemists. The document is based mainly on the recommendations of Australasian Association of Clinical Biochemists (AACB) Uncertainty of Measurement Working Group and is intended for all medical biochemistry laboratories in Croatia.

Highlights

Measurement uncertainty estimation results from the need for comparison of laboratory results
It means that measurement uncertainty gives us the range of values where we could expect a true value of the measurand with the same probability
We evaluated all the suggested approaches in measurement uncertainty estimation, and concluded that the most appropriate approach in laboratory medicine could be the one suggested by White et al which is supported by Burnett and Westgard [17,24,25,26,27]

Summary

Introduction

Measurement uncertainty estimation results from the need for comparison of laboratory results. Estimation of measurement uncertainty and its periodical verification ensure that a laboratory meets defined quality specifications of the methods, and offers the possibility to evaluate significant differences between two measurements. In laboratories the data on bias and uncertainty of calibrator are often not known or not available.

Results

Conclusion