Abstract
Background: Measurement uncertainty is a metrological concept to quantify the variability of measurement results. There are two approaches to estimate measurement uncertainty. In this study, we sought to provide practical and detailed examples of the two approaches and compare the bottom-up and top-down approaches to estimating measurement uncertainty.
Methods: We estimated measurement uncertainty of the concentration of glucose according to CLSI EP29-A guideline. Two different approaches were used. First, we performed a bottom-up approach. We identified the sources of uncertainty and made an uncertainty budget and assessed the measurement functions. We determined the uncertainties of each element and combined them. Second, we performed a top-down approach using internal quality control (IQC) data for 6 months. Then, we estimated and corrected systematic bias using certified reference material of glucose (NIST SRM 965b).
Results: The expanded uncertainties at the low glucose concentration (5.57 mmol/L) by the bottom-up approach and top-down approaches were ±0.18 mmol/L and ±0.17 mmol/L, respectively (all k=2). Those at the high glucose concentration (12.77 mmol/L) by the bottom-up and top-down approaches were ±0.34 mmol/L and ±0.36 mmol/L, respectively (all k=2).
Conclusions: We presented practical and detailed examples for estimating measurement uncertainty by the two approaches. The uncertainties by the bottom-up approach were quite similar to those by the top-down approach. Thus, we demonstrated that the two approaches were approximately equivalent and interchangeable and concluded that clinical laboratories could determine measurement uncertainty by the simpler top-down approach.
References
1. CLSI. Expression of measurement uncertainty in laboratory medicine; approved guideline. CLSI document EP29-A. Wayne, PA: Clinical and Laboratory Standards Institute, 2012.Search in Google Scholar
2. The International Organization for Standardization. Medical laboratories – requirements for quality and competence. ISO/TC 212/SC. International Standard ISO 15189. Geneva, Switzerland: ISO, 2012.Search in Google Scholar
3. Chen H, Zhang L, Bi X, Deng X. Two evaluation budgets for the measurement uncertainty of glucose in clinical chemistry. Korean J Lab Med 2011;31:167–71.10.3343/kjlm.2011.31.3.167Search in Google Scholar PubMed PubMed Central
4. Bercik Inal B, Koldas M, Inal H, Coskun C, Gumus A, Doventas Y. Evaluation of measurement uncertainty of glucose in clinical chemistry. Ann N Y Acad Sci 2007;1100:223–6.10.1196/annals.1395.023Search in Google Scholar PubMed
5. Ellison SL, Williams A, editors. Eurachem/CITAC guide: quantifying uncertainty in analytical measurement, 3rd ed. 2012. Available from: http://www.eurachem.org/index.php/publications/guides/quam. Accessed 5 October, 2014.Search in Google Scholar
6. BIPM, IEC, IFCC, ILAC, IUPAC, IUPAP, ISO, OIML (2012). International vocabulary of metrology – basic and general concepts and associated terms (VIM), 3rd ed. JCGM 200:2012. Available from: http://www.bipm.org/en/publications/guides/vim.html. Accessed 5 November, 2014.Search in Google Scholar
7. CLSI. Evaluation of precision performance of quantitative measurement methods; approved guideline, 2nd ed. Document EP5-A2. Wayne, PA: Clinical and Laboratory Standards Institute, 2004.Search in Google Scholar
8. Sadler WA. Variance function program (version 11.0). Available from: http://www.aacb.asn.au/professionaldevelopment/useful-tools/variance-function-program-version-110. Accessed 25 August, 2013.Search in Google Scholar
9. BIPM, IEC, IFCC, ILAC, IUPAC, IUPAP, ISO, OIML (2008). Evaluation of measurement data — guide to the expression of uncertainty in measurement. JCGM 100:2008. Available from: http://www.bipm.org/en/publications/guides/gum.html. Accessed 5 November, 2014.Search in Google Scholar
10. CLSI. Statistical quality control for quantitative measurement procedures: principles and definitions; approved guideline, 3rd ed. CLSI document C24-A3. Wayne, PA: Clinical and Laboratory Standards Institute, 2006.Search in Google Scholar
Supplemental Material
The online version of this article (DOI: 10.1515/cclm-2014-0801) offers supplementary material, available to authorized users.
©2015 by De Gruyter
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- Editorial
- Personalized medicine: moving from simple theory to daily practice
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