A-008 Verification of Interchangeability of Results for High-Sensitivity Troponin (TNIH) Between Atellica Solution® and Atellica CI® Analyzers

Abstract

Abstract Background Method intercomparison is an essential requirement that must be carried out in Clinical Laboratories before changing a method or instrument to verify the interchangeability of results. High-sensitivity troponin (TNIH) is an extraordinarily sensitive marker for detecting myocardial damage. Currently, it is determined in Atellica Solution® autoanalyzers (Siemens Healthineers) in our laboratory. After validating a new Siemens device, the Atellica CI®, it is essential to ensure the interchangeability of results in our laboratory accredited by ISO 15189: 2012. Objectives Our objective is to verify if the TNIH method in serum is interchangeable between the analyzers: Atellica Solution® and CI®. Methods A total of 77 serum samples from patients with TNIH values ranging from 2.5 to 25000 ng/L were processed by both analyzers. The statistical analysis of the results was performed using Passing-Bablok regression and Bland-Altman analysis, along with the Pearson correlation coefficient as a criterion to verify the adequacy of the sample size. Results are expressed with a 95% confidence interval. The statistical intercomparison study was conducted using Method Validator Version 1.19 Results In statistical analysis of Bland-Altman, no statistically significant differences were observed between the results obtained on both Atellica Solution® and CI 1900® analyzers since the 95% CI of the mean difference obtained includes the null value.Passing-Bablok regression shows a statistically significant, nearly negligible proportional systematic error, as the lower limit of the 95% CI is very close to 1; and a constant systematic error since the 95% CI of the intercept does not include the value 0 Conclusions Considering the 99th percentile established in our laboratory as a clinical decision value obtained after our own study of 45 ng/L, we do not exceed our quality specification for TNIH based on biological variability, which is 19.4%. Therefore, we can conclude that the determination of TNIH between both analyzers is interchangeable.