Abstract Number: PB0379
Meeting: ISTH 2021 Congress
Background: Prothrombin time (PT) is a cornerstone of the routine hemostasis panel. This means the test has to be available any time, in any laboratory, whatever the test platform. Quality management plans within clinical laboratories verify this consistency, but to ease this work, manufacturers can show the agreement by design.
Aims: The objective of this study was to show the correlation and agreement of PT/INR determination with STA-NeoPTimal when assessed on STart and STart Max semi-automated analyzers.
Methods: 86 individual samples, spreading the PT measuring range, were tested with one batch of STA-NeoPTimal on STart and STart Max analyzer in parallel (reagents and analyzers from Stago, Asnières-sur-Seine, France). This samples set included samples from patients under vitamin K antagonists or patients having any exogenous factor deficiency.
The ISI used for INR determination was the one provided by the manufacturer while the mean normal prothrombin time (MNPT) was the one determined locally.
Results: Linear regression was performed to evaluate correlations. Slope, intercept and Pearson correlation coefficients of those regressions are displayed in table 1.
| STart vs STart Max | Linear regression equation y = ax+b |
Pearson correlation coefficient (r) | Average bias | |
| Slope (a) | Intercept (b) | |||
| PT (sec) | 1.01 | -0.58 | 0.995 | 1% |
| INR | 1.01 | -0.04 | 0.996 | -0.89% to 01% depending on INR levels |
Conclusions: Results confirm a very high correlation and agreement of PT/INR determination with STA-NeoPTimal in its semi-automated methodology on both STart and STart Max instruments. These good results preclude easy method validation process and assay flexibility, for a possible instrument switch over time.
To cite this abstract in AMA style:
Le Goff G, Bouchain M, Carlo A, Beltran J. Comparability of PT Determination with STA-NeoPTimal on STart and STart Max Semi-automated Instruments [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/comparability-of-pt-determination-with-sta-neoptimal-on-start-and-start-max-semi-automated-instruments/. Accessed June 6, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/comparability-of-pt-determination-with-sta-neoptimal-on-start-and-start-max-semi-automated-instruments/