The importance of evaluating measurement uncertainty for troponin I

DOI: 10.4328/JCAM.5835 Received: 22.03.2018 Accepted: 26.04.2018 Published Online: 26.04.2018 Printed: 01.01.2019 J Clin Anal Med 2019;10(1): 1-4 Corresponding Author: Kübranur Ünal, Department of Biochemistry, Ankara Polatlı Public Hospital, Ankara, Turkey. E-Mail: dr.kubranur_unal@outlook.com ORCID ID: 0000-0001-7940-4590 Abstract Aim: Myocardial infarction can be life threatening and the early diagnosis of acute myocardial infarction is highly important. The measurement of cardiac troponin is the preferred way to establish the diagnosis of acute myocardial infarction. Measurement uncertainty provides quantitative estimates of the level of confidence that a laboratory has in its analytical precision of test results. The aim of this study is to present the importance of reporting hs-troponin I analysis results with measurement uncertainty estimation. Material and Method: The results of 16679 patients (8060 males and 8619 females) whose hs-troponin I results were analyzed in our laboratory in 2016 were retrospectively reviewed. The uncertainty of measurement was calculated according to Eurachem/CITAC Guide CG. The hs-troponin I analysis results were re-evaluated by estimation of measurement uncertainty. Results: Measurement uncertainty for hs-troponin I is estimated to be ± 19.60 %. In this study, 346 hs-troponin I analysis results (206 females and 140 males) which are above manufacturer recommended cutoff values might be below cutoff values if they were assessed based on measurement uncertainty. Also, 260 Troponin I analysis results (155 females and 105 males) which are below manufacturer recommended cutoff values cutoff values might be above cutoff values if they were assessed based on measurement uncertainty. The results of 606 out of 16679 patients (3.63%) were affected by uncertainty values. Discussion: Medical laboratories should calculate uncertainty of troponin tests and report this in conjunction with troponin results to help clinicians. A test result is not powerful enough without an assessment of its reliability. Therefore, hs-troponin I results which are close to cutoff values should be evaluated with uncertainty of measurement.