Performance verification of a new fibrinogen assay

Plasma fibrinogen (FIB), also known as factor I, plays a key role in the coagulation process. FIB testing in a clinical laboratory is crucial for coagulation screening and thrombolytic therapy. Here, we assessed the performance of a new, Chinese-made coagulation analyzer in the detection of FIB by comparing its precision and clinical feasibility with that of an imported system.

Blood samples were collected and plasmas were separated. The precision, linearity, reference interval, carryover rate, clinically reportable range, and clinical applicability of the domestic coagulation analyzer for FIB assay were assessed and validated based on the documents or industry standards issued by the United States Clinical and Laboratory Standards Institute (CLSI).

The within-batch precision CVs (coefficient of variation) for the low- and high-level specimens were 2.92% and 0.24%, respectively, while the total precision CVs were 3.05% and 1.81%, respectively; all of them met the experimental requirements. The linear range was validated to cover 1.0-6.5 g/L, and a good linear relationship was obtained within the measurement range (R2=0.9998). The reference interval was verified for adults and the carryover rate was also evaluated to be 0.68%. The clinically reportable range was 0.33-13.0 g/L. With a sample size of 180 cases, the methodological comparison showed a correlation coefficient (r) of 0.9886 between Mindray ExC810 and Sysmex CS5100. Furthermore, when the level of FIB was higher than 4.0 g/L or lower than 1.0 g/L, the 2 systems had an agreement rate of 100%.

Mindray ExC810 has a good performance for FIB assay in terms of precision, linearity, reference interval, carryover rate, and clinically reportable range. Methodological study showed that Mindray ExC810 has good agreement with Sysmex CS5100 and meets the requirements of laboratory testing. Therefore, Mindray ExC810 is suitable for FIB assay in clinical laboratory.