A comparison in the evaluation of measurement uncertainty in analytical chemistry testing between the use of quality control data and a regression analysis

Abstract

The evaluation of measurement uncertainties has been widely applied to the calibration of measurement instruments, whereas its application to tests, despite increasing requirements, is a more recent phenomenon. The generalization of the evaluation of measurement uncertainties to tests has been a gradual process, in line with changes in the requirements of the normative framework that regulates the accreditation of tests laboratories and also as the perceived good practices have evolved. The sole identification of the relevant sources of uncertainty was followed by the requirement to provide a simplified estimate of the measurement uncertainty, and it is now an accepted requirement to properly evaluate the expanded measurement uncertainty associated with any tests. In this study, the evaluation of measurement uncertainty associated with the determination of sulfate in water will be attempted using a procedure that includes linear regression, with the regression parameters provided with associated uncertainties, and a Monte Carlo method applied as a validation tool of the conventional mainstream evaluation method, concerning the approximations in terms of linearization of the model and the assumed shape of the output distribution introduced by this approach.

Fitting Models to Data: Residual Analysis, a Primer

“…Residual plots appear more and more frequently [32][33][34][35][36][37][38][39] in papers published in analytical journals. In general, these plots as well as those discussed in this chapter are very basic and Sentence Author(s)/reference 'Most assumptions required for the least squares analysis of data using the general linear model can be judged using residuals graphically without the need for formal testing'…”

Estimación de la incertidumbre en la calibración de esfigmomanómetros según OIML R16-1 desde una perspectiva de metrología legal

“…The estimation of uncertainty in the calibration is proposed according to what is established in a non-stochastic methodology such as the Guide to the Expression of Uncertainty in Measurement (GUM) [15]. This has been used in different processes from analytical chemistry tests [16], gamma-ray spectrometry [17], as well as in the application in measuring instruments such as electromagnetic compatibility tests [18].…”

A Practical Way to ISO/GUM Measurement Uncertainty for Analytical Assays Including In-House Validation Data

“…Sousa et al, 2012 [104] Application of various methodologies concerning the estimation of the standard uncertainty of a calibration curve used for the determination of sulfur mass concentration in fuels.…”