System performance evaluation of the cobas t 711 and cobas t 511 coagulation analyzers in routine laboratory settings

Abstract

Utility of coagulation analyzers in real-world settings depends on characteristics that are often not studied comprehensively. This study aimed to investigate the analytical performance, system functionality, practicability, consistency and throughput of two new automated coagulation analyzers in routine laboratory practice. Real-world settings were simulated in three major European hemostasis laboratories and multiple assays were performed in anonymized plasma samples in parallel with routine clinical practice on the cobas t 711 (high-throughput) and cobas t 511 (mid-throughput) analyzers using activated partial thromboplastin time (aPTT), aPTT Lupus, aPTT Screen, Antithrombin (AT), d-Dimer, Fibrinogen, Prothrombin Time (PT)-derived Fibrinogen, PT Owren, PT Rec (recombinant human thromboplastin reagent) and Thrombin Time assays. Precision was tested in a 21-day experiment and accuracy was compared with reference methods of the same laboratory. A number of experiments simulated challenging real-life situations. Pearson's correlation coefficient was more than 0.98 in all assays. Across assays, coefficients of variation ranged from 0.0 to 1.5% for intermediate precision; 0.2 to 3.0% for repeatability and 0.4 to 3.7% for total precision. Good between-run comparability was seen when testing samples under random conditions. Calculated maximum throughput was 197 and 387–402 tests/h for the cobas t 511 and 711 analyzers, respectively. Practicability met or exceeded user expectations in 98% of cases. In a simulated real-life setting of three major laboratories, the new cobas t 511 and cobas t 711 coagulation analyzers demonstrated a good functionality, practicability and performance and the throughput was high.