Comparison of the Two Coagulation Techniques: Thrombolyzer XRM and Diagon Coag XL

The aim of this study was to evaluate the performance characteristics of the Thrombolyzer XRM against the Diagon Coag XL during the exchange of the coagulation analyzer.

The Partial Thromboplastin Time (PTT) and prothrombin time (PT) measurements were performed by using the Thrombolyzer XRM and Diagon CoagXL analyzers. The precision, accuracy, method comparison, and reference range verification studies were performed on the Thrombolyzer XRM based on Clinical Laboratory Standards Institute guidelines.

The precision study was performed with normal and pathologic controls for the PT and PTT tests, all co-efficients of variation (%) were found ≤ 2.5%. In the accuracy study, both analyzers displayed less than 6.3% and 10.8% bias for PT and PTT tests, respectively. The method comparison study demonstrated good agreement for the Bland-Altman plots for PTT and PT with a bias of -2.0 and -3.3 between each analyzer, respectively. The Passing and Bablok analysis showed no significant differences for PTT and PT between each analyzer (p = 0.65 and p = 0.33, respectively). However, there was a proportional bias for PT with a slope of 1.40 (95% CI 1.2 - 1.8). The manufacturer ranges were acceptable as a result of the reference range verification study.

The routine coagulation analysis can be performed on the Thrombolyzer XRM with satisfactory precision and the obtained minor differences can be eliminated in future standardization studies.