Total Kolesterol, HDL-kolesterol, Trigliserid, Hesaplanmış LDL-kolesterol ve HDL dışı-kolesterol için Ölçüm Belirsizliği

Ölçüm belirsizliği, bir sonucun kalitesinin kantitatif bir göstergesi olup, ölçüm sonuçlarının güvenilirlik düzeyinde gerçekleştirildiğini gösterir. Çalışmamızda laboratuvarımızda sık istenen testlerden olan total kolesterol (TK), HDL-kolesterol (HDL-K), trigliserid (Tg), hesaplanmış LDL-kolesterol (LDL-K) ve HDL dışı-kolesterol (HDL dışı-K) için ölçüm belirsizliğini hesaplamak ve bu değerleri CLIA 2019 toplam izin verilen hata (%TEa) değerleriyle karşılaştırmak amaçlandı. Çalışmamız Karacabey Devlet Hastanesi Merkez Laboratuvarı’nda gerçekleştirildi. Nordtest kılavuzunda tanımlanan ve 6 adımdan oluşan hesaplama modeli ile ölçüm belirsizliği belirlendi. Mart-Ağustos 2020 dönemine ait iç ve dış kalite kontrol verileri kullanıldı. Ölçüm belirsizliği, TK, HDL-K ve Tg için %7, LDL-K için %12, HDL dışı-K için %10 olarak hesaplandı. TK, HDL-K ve Tg testleri için hesaplanan ölçüm belirsizliği, hedef %TEa değerinin altındadır. Ölçüm belirsizliğinin belirlenmesi ve düzenli olarak izlenmesi, laboratuvar içinde doğru sonuçlar üretmeyi ve kullanıcılara sonuçları yorumlamak için objektif bir araç sağlamayı amaçlar.

Anahtar Kelimeler:

toplam izin verilen hata, analitik faz, ölçüm belirsizliği, medikal laboratuvar, kalite kontrol

Measurement Uncertainty for Total Cholesterol, HDL-cholesterol, Triglycerides, Calculated LDL-cholesterol and non-HDL-cholesterol

Measurement uncertainty is a quantitative indicator of the quality of a result, indicates that the measurement results are performed at the level of reliability. It was aimed to calculate the measurement uncertainty for total cholesterol, HDL-cholesterol, triglycerides, calculated LDL-cholesterol, and non-HDL-cholesterol, which are frequently ordered tests in our laboratory, and to compare these values with CLIA 2019 allowable total error (TEa%) values. Our study was performed in the Central Laboratory of Karacabey State Hospital. The measurement uncertainty was determined with the calculation model defined in the Nordtest guide consisting of 6 steps. Internal and external quality control data were recorded from March to August 2020. The measurement uncertainty was calculated as 7% for total cholesterol, HDL-cholesterol and triglycerides, 12% for LDL-cholesterol and 10% for non-HDL-cholesterol. Measurement uncertainty for total cholesterol, HDL-cholesterol and triglycerides was found below the targeted TEa%. Measurement uncertainty estimation and its periodical verification aim to produce accurate results within the laboratory and provide users with an objective tool to interpret the results.

Keywords:

allowable total error, analytical phase, measurement uncertainty, medical laboratory, quality control,

PDF

___

1. International vocabulary of metrology – basic and general concepts and associated terms (VIM), 3rd ed. JCGM 2012:200. Available from: https://www.bipm.org/en/committees/jc/jcgm/publications. Erişim Mart 9, 2021.
2. Ellison SL, Williams A. Eurachem guide: quantifying uncertainty in analytical measurement. Eurachem, 3rd ed. 2012. Available from: https://www.eurachem.org/images/stories/Guides/pdf/QUAM2012_P1.pdf. Erişim Mart 9, 2021.
3. Infusino I, Panteghini M. Measurement uncertainty: friend or foe? Clin Biochem. 2018;57:3-6. doi: 10.1016/j.clinbiochem.2018.01.025.
4. Ćelap I, Vukasović I, Juričić G, Šimundić AM. Minimum requirements for the estimation of measurement uncertainty: Recommendations of the joint Working group for uncertainty of measurement of the CSMBLM and CCMB. Biochem Med (Zagreb). 2017;27 (3):030502. https://doi.org/10.11613/BM.2017.030502.
5. Clinical and Laboratory Standards Institute (CLSI). Expression of measurement uncertainty in laboratory medicine - Approved Guideline. CLSI document C51-A. Wayne, USA: CLSI, 2012.
6. The Royal College of Pathologists of Australasia. Uncertainty of measurement. Guideline No 2/2004. Available from: https://hercwules.files.wordpress.com/2013/07/rcpa-uncertainty.pdf. Erişim Mart 9, 2021.
7. Working Group 1 of the Joint Committee for Guides in Metrology. Evaluation of measurement data — Guide to the expression of uncertainty in measurement. First ed. JCGM 100:2008. Available from: http://www.iso.org/sites/JCGM/GUM/JCGM100/C045315e-html/C045315e.html?csnumber=50461. Erişim Mart 9, 2021.
8. American Association for Laboratory Accreditation. Policy on estimating measurement uncertainty for ISO 15189 testing laboratories. P903, 2014. Available from: https://www.a2la.org/policies/15189_P903.pdf. Erişim Mart 9, 2021.
9. National Pathology Accreditation Advisory Council (NPAAC). Requirements for the estimation of measurement uncertainty. 2007 ed. Available from: http://www.health.gov.au/internet/main/publishing.nsf/Content/B1074B732F32282DCA257BF0001FA218/$File/dhaeou.pdf. Erişim Mart 9, 2021.
10. ISO 15189. Medical laboratories - Requirements for quality and competence. Geneva, Switzerland: International Organization for Standardization; 2012.
11. Westgard JO, Carey RN, Wold S. Criteria for judging precision and accuracy in method development and evaluation. Clin Chem 1974;20:825–33.
12. Sağlıkta Kalite ve Akreditasyon Daire Başkanlığı. Sağlıkta Kalite Standartları – Hastane. Available from: http://dosyamerkez.saglik.gov.tr/Eklenti/3460,skshastanesetiv5r1pdf.pdf?0. Erişim Mart 9, 2021.
13. Arslan B, Çobanoğlu İ, Dinçel A. Status of lipid profile tests according to the last consensus paper. Turkish Journal of Biochemistry. 2020;45(3):337-338. https://doi.org/10.1515/tjb-2020-0172.
14. The Task Force for the management of dyslipidaemias of the European Society of Cardiology (ESC) and European Atherosclerosis Society (EAS). 2019 ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. European Heart Journal. 2020;41:111-188. doi:10.1093/eurheartj/ehz455.
15. Magnusson B, Naykki T, Hovind H, Krysell M. Handbook for calculation of measurement uncertainty in environmental laboratories, NordTest Report TR 537. NORDTEST, Finland, 2004.
16. Clinical Laboratory Improvement Amendments of 1988 (CLIA) Proficiency Testing Regulations Related to Analytes and Acceptable Performance. Federal Register. 2019 Feb 4;84.
17. White GH. Basics of estimating measurement uncertainty. Clin Biochem Rev. 2008;29(Suppl 1):53-60.
18. Quality Requirements. Desirable Specifications for Total Error, Imprecision, and Bias, derived from intra- and inter-individual biologic variation. Available from: https://www.westgard.com/biodatabase1.htm. Erişim Mart 9, 2021.
19. Bal C, Serdar MA, Güngör OT, et al. Calculation of measurement uncertainty of biochemical parameters. Turk J Biochem. 2014;39(4):538-43. doi:10.5505/tjb.2014.04127.
20. Balık AR, Gücel F. Evaluation of 20 clinical chemistry and 12 immunoassay analytes in terms of total analytical error and measurement uncertainty. Scand J Clin Lab Invest. 2021 Jul 27:1-6. doi: 10.1080/00365513.2021.1955294.
21. Jones GR. Laboratory analytical quality – the process continues. Clin Chem Lab Med. 2016;54:1275–6. https://doi.org/10.1515/cclm-2016-0321.
22. Tate JR, Plebani M. Measurement uncertainty – a revised understanding of its calculation and use. Clin Chem Lab Med. 2016;54(8):1277–79. DOI 10.1515/cclm-2016-0327.
23. Sciacovelli L, Panteghini M, Lippi G, et al. Defining a roadmap for harmonizing quality indicators in Laboratory Medicine: a consensus statement on behalf of the IFCC Working Group "Laboratory Error and Patient Safety" and EFLM Task and Finish Group "Performance specifications for the extra-analytical phases". Clin Chem Lab Med. 2017;55(10):1478-88. DOI: 10.1515/cclm-2017-0412.