The comparison between the results of turbidimetric method for c-reactive protein measurement using different instruments

Abstract

C-reactive protein (CRP) is considered a marker of chronic inflammation and also a mediator of the atherosclerotic process. The purpose of this study is to compare the results of three quantitative immunoturbidimetric method used to measure CRP amounts in patient serum samples in a clinical laboratory. Freshly collected patient serums (n=100) were analyzed with 2 different analyzer (Siemens Advia 1800 and Abbott Architect C 8000) and 3 different reagents (Siemens, Sentinel, Archem). In order to determine whether they provide equivalent results in terms of traceability, the EP09-A3 guideline was used, and comparisons were evaluated within the scope of this standard. Limit of quantification (LoQ), Inter27 assay, Intra-assay, precision studies have been done. The relationship between these three reagents was determined by regression analysis and Bland Altman method. Regression coefficiencies between these three methods were found: ArchemSentinel r2=0,9987, Archem – Siemens r2=0,9986 and Sentinel – Siemens r2=0,9984. Regression equations between Archem-Sentinel y=-0,1359+1.0035x, between Archem-Siemens y=-0,02646+1,002x and between Sentinel – Siemens y=0,1326+0,9978x were found. For the first time in the literature, our results indicated that these three immunoturbidimetric methods were compatible.