Background: Its increasing clinical importance has turned 25-hydroxy-Vitamin D (25(OH)D) into an indispensable test in clinical laboratories. In this study, we aimed to analyze the analytical performances of two widely used immunoassays, namely new restandardized Abbott product Architect 25-OH Vitamin D test and the Beckman Coulter product Access 25(OH) Vitamin D Total Test by making comparisons with the reference method liquid chromatography tandem mass spectrometry (LC-MS/MS).
Methods: The new restandardized Architect I2000SR System (Abbott Laboratories, IL, USA; ref 5P02) and Access2 (Beckman Coulter, Brea, CA, USA; ref B24838) immunoassay were compared with LC-MS/MS (Shimadzu LCMS-8030, Kyoto, Japan) method 25(OH)D test for precision and reproducibility in 90 serum samples. In comparison with reference method, Deming Regression analysis and Bland Altman graphs were used. Results: Within run coefficient of variation (CV%) for Architect was found to be lower than 3.1%. Within run coefficient of variation (CV%) for Access2 was lower than 7.04%.
When compared with LC-MS/MS, R value of Architect 25-OH Vitamin D kit was 0.911 (intercept 1.62, slope 1.06), mean bias was -0.04% and for Access 25(OH) Vitamin D Total kit, R value was 0.841 (intercept 9.43, slope 0.92) and mean bias of 6.9%.
Conclusions: When renewed 5P02 Abbott Architect 25(OH)D and Beckman Coulter Access2 25(OH)D Total tests were compared with LC-MS/MS method in our study, they were found to have appropriate analytical values.