Evaluation of Measurement Uncertainties of Immunoassays Analytes According to Biological Variation Databases

Background: Quality control (QC) of analytical measurement is a stage used for the evaluation of whether the measurement method is appropriate to the standards required for patient care. QC encompasses internal (IQC) and external laboratory content (EQC). Measurement uncertainty (MU) is an important issue that expresses each analyte's measurement. Autoanalyzer's, calibrators, and control materials of analytes, reagents, measures contribute to MU. The aim of this study was to calculate the measurement uncertainty of nineteen immunoassay analytes in the biochemistry laboratory and to evaluate the compatibility of these measurements with the analytical quality targets derived from different biological variations. Methods: In the study, Cobas 6000 Modular Analysis Series (Roche Diagnostics, USA) autoanalyzer was used. IQC data of the analytes between August 2017 and January 2018 were used together with the monthly EQC data of June 2017 to January 2018. NORDTEST guideline was used to calculate the MU. "Desirable" analytical quality goals of each analyte with Fraser's formula were calculated and evaluated the limits from EuBIVAS (The European Biological Variation Study) and Ricos's biological variation databases. Results: MU of fT(4) was seen to be higher than TEa (Total Allowable Analytical Error)(Ricos) in our study. MU of fT(4) was seen to be lower than TEa(EuBIVAS) (MUfT4: 9.20%, TEa(Ricos): 8.00%; TEa(EuBIVAS): 9.92%). Conclusions: The analytical quality performances of the analytes included in the study turned out to be sufficient in our laboratory.