Evaluation of Measurement Uncertainty of Some Biochemical Parameters According to ISO/TS 20914 Guidance

Aim: Laboratory tests are an important part of clinical diagnostic decision. Therefore, measurement
uncertainty stands out in the context of the accuracy of the laboratory results. In the study, different
quality objectives and results were evaluated by investigating the measurement uncertainty of 29 routine
biochemistry analytes.
Material and Methods: The measurement uncertainty calculation model of 29 analytes were analyzed
with the Mindray BS-800 autoanalyzer between October 2020 and April 2021, and evaluated according
to ISO/TS 20914 Guideline. The external uncertainty and measurement uncertainties consist of definition
of the measured values, determination of the factors affecting the measurement, method measurement
uncertainty, calibration uncertainty , and quality control data were determined.
Results: The measured analytes as triglyceride, iron, phosphorus, GGT, creatine kinase, uric acid, lipase
and CRP were compatible with EFLM and Ricos total allowable error (TEa%) values at both levels. ALT
was compatible with level 2 and level 1 according to Ricos, amylase, AST, total cholesterol, HDL and total
bilirubin were compatible with level 2 according to Ricos. In addition, LDH and BUN were compatible with
level 2 according to EFLM.
Conclusion: Measurement uncertainty shows the distribution of measurement results which displays an
important role in the evaluation of measurement of laboratory tests. In our study, it was determined that
triglyceride, iron, phosphorus, GGT, creatine kinase, uric acid, lipase and CRP analytes were compatible
with both levels according to the total allowable error (TEa%) of EFLM and Ricos. Also, it was observed
that the other parameters were not compatible with both levels. Further and comprehensive studies are
needed.