Abstract
BACKGROUND: The results of cardiac troponin I (cTnI) methods used in the diagnosis of acute myocardial infarction (AMI) are highly variable. In this study, it was aimed to compare the analytical performance of the Mindray CL-series TnI method with the Beckman Coulter-Access II AccuTnI+3 method. METHODS: Analytical performance and method comparison experiments for cTnI measurement with Mindray CL-1000i and Beckman Coulter-Access II instruments were with the Clinical and Laboratory Standards Institute (CLSI) documents EP15-A3 and EP9-A3. Precision studies were performed with commercially available third-party quality control (QC) materials. Method comparison experiments were performed by using patient samples. Furthermore, the limit of quantification (LoQ), total analytical error (TAE), and sigma metrics of both methods was determined. RESULTS: The repeatability CV% for the three levels of Mindray CL-series TnI were 1.86, 1.75, and 1.08, while within the laboratory, CV% values were 3.36, 5.27, and 5.82. The quantification limits for Mindray CL-series and Beckman AccuTnI+3 were found to be 0.0085 and 0.0366 ng/mL with a CV level of less than 10%, respectively. The Mindray CL-series TnI results in the method comparison study were higher compared to the Beckman Coulter Access II AccuTnI+3 method. CONCLUSIONS: With low repeatability, low bias, and low LoQ, The Mindray CL-series cTnI method shows it may be used safely in its category. The significant difference between the two methods in the method comparison study reveals cTnI methods in the market should be standardized to ensure global traceability.