Uncertainty of Measurement in Laboratory Medicine

Abstract

SummaryAn adequate assessment of the measurement uncertainty in a laboratory medicine is one of the most important factors for a reliable interpretation of the results. A large number of standards and guidelines indicate the need for a proper assessment of the uncertainty of measurement results in routine laboratory practice. The available documents generally recommend participation in the proficiency schemes/ external quality control, as well as the internal quality control, in order to primarily verify the quality performance of the method. Although all documents meet the requirements of the International Standard, ISO 15189, the standard itself does not clearly define the method by which the measurement results need to be assessed and there is no harmonization in practice regarding to this. Also, the uncertainty of measurement results is the data relating to the measured result itself, but all factors that influence the interpretation of the measured value, which is ultimately used for diagnosis and monitoring of the patient's treatment, should be taken into account. So in laboratory medicine, an appropriate assessment of the uncertainty of the measurement results should have the ultimate goal of reducing diagnostic uncertainty. However, good professional laboratory practice and understanding analytical aspects of the test for each individual laboratory is necessary to adequately define the uncertainty of measurement results for specific laboratory tests, which helps to implement good clinical practice. Also, setting diagnoses in medicine is a decision with a certain degree of uncertainty, rather than statistically and mathematically calculated conclusion.

Verification of quantitative analytical methods in medical laboratories

“…There have been several publications discussing the guidelines of method validation and verification adopted by national and international organizations, regu lated and used by ISO 17025, ISO 15189 or by the Clinical Laboratory Improvement Amendments of 1988 (CLIA 88) [7] either generally [7] [8] [9] [10] [11] [12] [13] [14] [15] or specifically in the analytical chemistry [16] [17] , toxicology [18] , chemical pathology [19] , food and drugs industry [20] [21] .…”

Interpol review of toxicology 2016–2019

“…Milinković et at [ 18 ] described the significance of an appropriate assessment of the uncertainty of the measurement results in laboratory medicine to reduce diagnostic uncertainty. Several approaches in deriving proper measurement uncertainty from internal quality control data acquired in clinical laboratories were presented by Ceriotti [ 19 ].…”

Reference Interval of Some Liver Function Parameters in Adults of a Section of Indian Population and Age-Gender Variation

“…Although measurement uncertainties in total protein and albumin are generally <5% [12] and the optimal imprecision is 3% [13], if an arbitrarily expanded threshold of 10% of the highest mean is considered the margin of error due to intraindividual sampling fluctuations and measurement uncertainties, the difference between the highest mean and the lowest mean across age groups was greater than this threshold for most parameters in both males and females. If this is considered evidence of the presence of age-trend and p values are disregarded, it seems that, on average, age did affect these values.…”