Steve Kitchen1, Ulrich Geisen2, Janos Kappelmayer3, Peter Quehenberger4, Julia Drieß2, Anna Lowe1, Robert Jones1, Jana G Boehm5, Gabrielle Miles6, Gergely Rozsnyai7. 1. Sheffield Haemostasis and Thrombosis Centre, Sheffield, UK. 2. Institute for Clinical Chemistry and Laboratory Medicine, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany. 3. Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary. 4. Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria. 5. Roche Diagnostics GmbH, Mannheim, Germany. 6. Roche Diagnostics Inc., Indianapolis, Indiana. 7. Roche Diagnostics International Ltd, Rotkreuz, Switzerland.
Abstract
INTRODUCTION: New methods for coagulation tests require careful assessment before routine use. We evaluated the analytical performance of five new coagulation assays for measuring prothrombin time (PT) and activated partial thromboplastin time (aPTT). METHODS: PT Rec, PT Owren, aPTT, aPTT Lupus and aPTT Screen assays (Roche Diagnostics) were evaluated on cobas t 711 and cobas t 511 analysers (Roche Diagnostics) at four European centres. Analytical performance and method comparisons with relevant commercially available assays were performed to Clinical Laboratory Standards Institute guidelines using residual anonymized samples. Lot-to-lot comparison and equivalency of the cobas t analysers were also assessed; reference ranges were determined using samples from apparently healthy volunteers. RESULTS: Overall, coefficients of variation were ≤1.3% for within-run precision and ≤6.3% for total reproducibility across all sites. Deming regression analyses showed good agreement between each assay (cobas t 711) and respective comparator method (Pearson's r: 0.964-0.999, n > 120 samples/assay/site). Passing-Bablok regression analyses demonstrated equivalence of the two cobas t platforms for use with each assay (Pearson's r ≥ 0.995). Lot-to-lot consistency was high for all assays and comparisons (Pearson's r ≥ 0.998). Reference ranges (2.5th-97.5th percentiles; n = 200 samples/assay) in seconds were 8.4-10.6 (PT Rec), 18.2-27.2 (PT Owren), 23.6-30.6 (aPTT), 24.1-31.7 (aPTT Lupus) and 23.9-33.2 (aPTT Screen). CONCLUSION: Based on the excellent analytical performance and good agreement with relevant comparator methods, the five coagulation assays on the novel cobas t 711 and cobas t 511 analysers are suitable for routine use in core laboratories.
INTRODUCTION: New methods for coagulation tests require careful assessment before routine use. We evaluated the analytical performance of five new coagulation assays for measuring prothrombin time (PT) and activated partial thromboplastin time (aPTT). METHODS: PT Rec, PT Owren, aPTT, aPTT Lupus and aPTT Screen assays (Roche Diagnostics) were evaluated on cobas t 711 and cobas t 511 analysers (Roche Diagnostics) at four European centres. Analytical performance and method comparisons with relevant commercially available assays were performed to Clinical Laboratory Standards Institute guidelines using residual anonymized samples. Lot-to-lot comparison and equivalency of the cobas t analysers were also assessed; reference ranges were determined using samples from apparently healthy volunteers. RESULTS: Overall, coefficients of variation were ≤1.3% for within-run precision and ≤6.3% for total reproducibility across all sites. Deming regression analyses showed good agreement between each assay (cobas t 711) and respective comparator method (Pearson's r: 0.964-0.999, n > 120 samples/assay/site). Passing-Bablok regression analyses demonstrated equivalence of the two cobas t platforms for use with each assay (Pearson's r ≥ 0.995). Lot-to-lot consistency was high for all assays and comparisons (Pearson's r ≥ 0.998). Reference ranges (2.5th-97.5th percentiles; n = 200 samples/assay) in seconds were 8.4-10.6 (PT Rec), 18.2-27.2 (PT Owren), 23.6-30.6 (aPTT), 24.1-31.7 (aPTT Lupus) and 23.9-33.2 (aPTT Screen). CONCLUSION: Based on the excellent analytical performance and good agreement with relevant comparator methods, the five coagulation assays on the novel cobas t 711 and cobas t 511 analysers are suitable for routine use in core laboratories.
Authors: Steve Kitchen; Moniek de Maat; Michael Nagler; Robert Jones; Anna Lowe; John Burden; Kai Groneberg; Gergely Rozsnyai Journal: Blood Coagul Fibrinolysis Date: 2020-10 Impact factor: 1.061