Reagent Carryover Studies: Preventing Analytical Error with Open Clinical Chemistry Systems

Abstract Background The importance of managing analytical quality in clinical laboratories is known. Goal-setting models are critical for analytical quality management, along with correctly implemented error models. However, the methods used to determine analytical performance and more importantly, the relevant analytical quality goals are open to discussion. Our aim was to compare the analytical performance characteristics of routine clinical chemistry tests with different goal-setting models which was proposed by various establishments. In addition, to provide a perspective to Turkish total analytical error (TAE) circular letter that compulsory to calculate from 2016. Materials and methods This study was performed by the data obtained from the internal and external quality control of clinical chemistry tests which were measured by Roche Cobas c501 biochemistry analyzer. TAE calculated with TAE% = 1.65 ×(CV%) + Bias% formula. Nordtest uncertainty model was used in the calculation of measurement uncertainty (MU). In this context, total analytical error was evaluated with biological variation (BV), RCPA, CLIA and Turkish allowable total error (ATE) goals. Measurement uncertainty was evaluated with only permissible measurement uncertainty (pU%) goal. Results In our study, RCPA goals are the most stringent, followed by the BVEuBIVAS, BVRicos, pU%, CLIA and finally the ATETurkey goals coming in last. In cumulatively, BVEuBIVAS goals were 18.3% lower than BVRicos for evaluated parameters. Conclusion The balance between applicability and analytical assurance of goals should be well ensured when determining goal-setting models. Circular letter (2016/18) creates awareness to the analytical quality management but still open to development. Biological variation dependent total allowable error model never designed to be used as benchmarks for measurement uncertainty and it is not methodologically appropriate for assessing measurement uncertainty which was estimated by the Nordtest method. Also considered that, the use of “permissible MU” is more methodologically appropriate in the evaluation of measurement uncertainty.

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Intraperson Variability

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456327801500114 ◽

1978 ◽

Vol 15 (1-6) ◽

pp. 49-54 ◽

Cited By ~ 3

Author(s):

D. B. Morgan

Keyword(s):

Steady State ◽

Total Variation ◽

Clinical Chemistry ◽

Single Test ◽

Analytical Error ◽

Analytical Technique ◽

A Value ◽

The Common

summary In a person in a steady state the set of values obtained for a test carried out on a series of samples will show fluctuation about a value (the setting). In practice a single test value is usually taken as an estimate of the setting. The general consequences of this approximation are discussed in relation to the various uses of data in diagnosis, and illustrated for the common measurements of clinical chemistry. The magnitude of these consequences depends on the proportion of the total variation in a group of persons which is caused by these fluctuations in the person—within-person variation (Varwp). When the proportion is high the aim should be to reduce Varwp. When Varwp is high because of analytical error, then improved analytical technique or replicate analysis is required. Otherwise standardised techniques and conditions for venepuncture or, as a last resort, repeated samplings are necessary. These problems are discussed in relation to the detection of hypokalaemia.

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Irregular analytical errors in diagnostic testing – a novel concept

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2017-0454 ◽

2018 ◽

Vol 56 (3) ◽

pp. 386-396 ◽

Cited By ~ 9

Author(s):

Michael Vogeser ◽

Christoph Seger

Keyword(s):

Quality Control ◽

Measurement Uncertainty ◽

Measurement System ◽

Clinical Chemistry ◽

Individual Sample ◽

Reference Measurement ◽

Analytical Error ◽

The Individual ◽

Analytical Errors ◽

Reference Measurement System

AbstractBackground:In laboratory medicine, routine periodic analyses for internal and external quality control measurements interpreted by statistical methods are mandatory for batch clearance. Data analysis of these process-oriented measurements allows for insight into random analytical variation and systematic calibration bias over time. However, in such a setting, any individual sample is not under individual quality control. The quality control measurements act only at the batch level. Quantitative or qualitative data derived for many effects and interferences associated with anindividualdiagnostic sample can compromise any analyte. It is obvious that a process for a quality-control-sample-based approach of quality assurance is not sensitive to such errors.Content:To address the potential causes and nature of such analytical interference in individual samples more systematically, we suggest the introduction of a new term called theirregular(individual)analytical error. Practically, this term can be applied in any analytical assay that is traceable to a reference measurement system. For an individual sample an irregular analytical error is defined as an inaccuracy (which is the deviation from a reference measurement procedure result) of a test result that is so high it cannot be explained by measurement uncertainty of the utilized routine assay operating within the accepted limitations of the associated process quality control measurements.Summary:The deviation can be defined as the linear combination of the process measurement uncertainty and the method bias for the reference measurement system. Such errors should be coinedirregular analytical errorsof the individual sample. The measurement result is compromised either by an irregular effect associated with the individual composition (matrix) of the sample or an individual single sample associated processing error in the analytical process.Outlook:Currently, the availability of reference measurement procedures is still highly limited, but LC-isotope-dilution mass spectrometry methods are increasingly used for pre-market validation of routine diagnostic assays (these tests also involve substantial sets of clinical validation samples). Based on this definition/terminology, we list recognized causes of irregular analytical error as arisk catalogfor clinical chemistry in this article. These issues include reproducible individual analytical errors (e.g. caused by anti-reagent antibodies) and non-reproducible, sporadic errors (e.g. errors due to incorrect pipetting volume due to air bubbles in a sample), which can both lead to inaccurate results and risks for patients.

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Evaluation of 20 clinical chemistry and 12 immunoassay analytes in terms of total analytical error and measurement uncertainty

Scandinavian Journal of Clinical and Laboratory Investigation ◽

10.1080/00365513.2021.1955294 ◽

2021 ◽

pp. 1-6

Author(s):

Ahmet Rıfat Balık ◽

Funda Gücel

Keyword(s):

Measurement Uncertainty ◽

Clinical Chemistry ◽

Analytical Error

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Setting analytical goals for random analytical error in specific clinical monitoring situations

Clinical Chemistry ◽

10.1093/clinchem/36.9.1625 ◽

1990 ◽

Vol 36 (9) ◽

pp. 1625-1628 ◽

Cited By ~ 74

Author(s):

C G Fraser ◽

P Hyltoft Peterson ◽

M L Larsen

Keyword(s):

Diabetes Mellitus ◽

Renal Failure ◽

Chronic Renal Failure ◽

Clinical Chemistry ◽

Statistical Significance ◽

Test Results ◽

Analytical Error ◽

Analytical Goals ◽

Analytical Imprecision ◽

Clinically Significant

Abstract Strategies abound for the setting of analytical goals in clinical chemistry. Many, especially those more recently proposed for particular clinical situations, are concerned with tests used in diagnosis. We suggest a general theory for the setting of goals in situations that specifically involve the monitoring of individuals. Goals are calculated from the formula CVA less than [(delta c 2/2Z2)-CVB2]1/2, where CVA is the analytical imprecision (as coefficient of variation, CV); delta c is the percentage change in serial results that is considered clinically significant; Z is the Z-statistic, which depends only on the probability selected for statistical significance; and CVB is the average inherent within-subject biological variation (as CV). Examples given show applications in hematology and in monitoring diabetes mellitus, chronic renal failure, and hepatitis. The derived goals are for total random analytical error (imprecision and intermittent systematic variation), and provide objective criteria that should be achieved in practice. The effect of analytical variability on both variability in test results and the probability that a stated change can be considered significant should be calculated whether or not the goals are attained.

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Drug-interference in clinical chemistry analyses pseudohypertriglyceridaemia

The Journal of Clinical and Scientific Research ◽

10.15380/2277-5706.jcsr.13.045 ◽

2014 ◽

Vol 3 (2) ◽

pp. 153

Author(s):

P Swathi ◽

M Prasanth ◽

MM Suchitra ◽

AparnaR Bitla

Keyword(s):

Clinical Chemistry ◽

Drug Interference

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RETRACTION NOTE: Les structures des phrases dans les tracts du mai 1968

Digital Press Social Sciences and Humanities ◽

10.29037/digitalpress.43323 ◽

2019 ◽

Vol 3 ◽

pp. 00047

Author(s):

Nokiamy Sesena Tamba ◽

Myrna Laksman-Huntley

Keyword(s):

Social Sciences ◽

Public Domain ◽

Background Color ◽

Font Size ◽

Analytical Error ◽

Social Sciences And Humanities ◽

Retracted Article ◽

Du Mai ◽

Web Archive ◽

Digital Press

As of October 15, 2019, the following article is being retracted from the UGM Digital Press Social Sciences and Humanities series.“Les structures des phrases dans les tracts du mai 1968” by Nokiamy Sesena Tamba and Myrna Laksman-Huntley, Social Sciences and Humanities Series Vol 3: 00033, Proceeding of Conférence internationale sur le français 2018, Joesana Tjahjani, Merry Andriani, Sajarwa, Wening Udasmoro (eds) DOI: <a href="https://doi.org/10.29037/digitalpress.43306" target="_blank" style="background-color: rgb(255, 255, 255); font-size: 1rem;">https://doi.org/10.29037/digitalpress.43306</a>The original article is registered through this URL <a href="https://digitalpress.ugm.ac.id/article/306" target="_blank">https://digitalpress.ugm.ac.id/article/306</a>as decided by authors and conference organizers on the basis of analytical error. It may encourage potential misleading circulation of information in the future.On the following exchange of information with the publisher, it has been decided that the article will be retracted.The retracted article will remain in public domain, that is maintaining its appearance on UGM Digital Press web archive and the Conférence internationale sur le français 2018 printed version. However, it will receive a watermark to accentuate its retracted status.

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