Verification of quantitative analytical methods in medical laboratories

Abstract

Background: Globally, all medical laboratories seeking accreditation should meet international quality standards to perform certain specific tests. Quality management program provides disciplines targeted to ensure that quality standards have been implemented by a laboratory in order to generate correct results. The hallmark of the accreditation process is method verification and quality assurance. Before introducing a new method in your laboratory, it is important to assess certain performance characteristics that reflect the concept of method verification. Methods: In this review, we illustrated how to verify the performance characteristics of a new method according to the recent guidelines. It includes an assessment of precision, trueness, analytical sensitivity, detection limits, analytical specificity, interference, measuring range, linearity, and measurement uncertainty. Conclusions: Although the presence of several updated guidelines used to determine the performance characteristics of new methods in clinical chemistry laboratories, the real practice raised several concerns with the application of these guidelines which in need for further consideration in the upcoming updates of these guidelines.

RGB-based colorimetric method for the analysis of water alkalinity using Cordyline fruticosa extracts as visual indicator

“…The linear working range was between 40 to 160 ppm of CaCO3 with a calibration sensitivity of 5 x 10 -3 ppm and a coefficient of correlation (r 2 ) = 0.998 as shown in since the obtained r 2 is within 0.998 to 1.000 [34], [35]. The LOD, which is the lowest concentration detected but not exactly quantified [34], [35] was 39 ppm. While the LOQ or the quantifiable concentration usually higher than LOD [34], [35] was 117 ppm.…”

“…The LOD, which is the lowest concentration detected but not exactly quantified [34], [35] was 39 ppm. While the LOQ or the quantifiable concentration usually higher than LOD [34], [35] was 117 ppm. The percent recovery for the proposed method was 89.79% which falls within the acceptable criteria for the analysis of anions in drinking water (85%-115%) [27].…”

Reducing the need for repeating urine drug testing with the gray zone determined by the measurement uncertainty

“…The area around the cut-off value, known as the "grey zone," is defined to express the uncertainty of results [7] [8] . Using a grey zone to classify screening immunoassay test results reduces the risk of misclassification; however, this is not systematically needed [7] .…”

“…The area around the cut-off value, known as the "grey zone," is defined to express the uncertainty of results [7] [8] . Using a grey zone to classify screening immunoassay test results reduces the risk of misclassification; however, this is not systematically needed [7] . Furthermore, its use is not required by the ISO 15189 guideline, which specifies the requirements for the accreditation of medical laboratories [9] .…”

The Methodology for the Reliability Evaluation of the Signal Processing Methods Used for the Dispersion Estimation of Lamb Waves

“…This makes it difficult to interpret the distribution of the results and to The general principles and sequence of the mathematical and experimental stages will facilitate the verification analysis of any signal processing method used for the dispersion evaluation of Lamb waves and expand understanding about the measurement reliability, peculiarities of method validation, and verification. These provisions will complement the general guidelines [19], [20], [28], [29] that present a discussion of the characteristics that should be considered during the verification or validation of procedures. The aim of this work is to develop a methodology for verification of the signal processing methods applied to reconstruct the dispersion curves of the phase and group velocities of Lamb waves and the accuracy assessment according to the requirements of ISO 17025.…”