A-220 Method Intercomparison Study between Atellica Solution® and CI® Analyzers for HDL and LDL Methods

Abstract Background After validating a new Siemens equipment, the Atellica CI®, it is essential to ensure result interchangeability in our laboratory accredited by ISO 15189:2012. Objectives verify if the results of the HDL and LDL methods measured by Atellica Solution® and CI® analyzers are interchangeable and could be used interchangeably on both instruments Methods 40 patient samples were selected for each assay, with results distributed across the entire measurement range and analyzed by both instruments. Result evaluation was conducted using the statistical program Method Validator v.19. To determine the degree of agreement between the instruments, a Bland-Altman mean difference analysis and a Passing-Bablok regression were performed. Statistics are expressed with their 95% confidence intervals (CI). Results HDL: After analyzing the Bland-Altman differences, a systematic error was found as the mean difference between the results obtained by Atellica Solution® and CI® was 0.686, with higher results in CI 1900®. Regarding the Passing Bablok analysis, constant systematic differences were observed as the confidence interval of the intercept does not include the zero value, and statistically significant proportional differences based on the slope whose 95% CI does not include the value 1.LDL: After analyzing the Bland-Altman differences, a systematic error was found as the mean difference between the results obtained by Atellica and CI® was -3.16, with higher results in Atellica Solution®. Regarding the Passing Bablok analysis, there were no systematic differences of constant type as the confidence interval of the intercept includes the zero value, but there were proportional differences based on the slope whose 95% CI does not include the value 1. Conclusions After evaluating the results, it is concluded that Atellica Solution® and CI® analyzers are interchangeable for HDL and LDL assays despite the presence of a systematic error, as the observed difference is not clinically significant.