Thrombosis and Haemostasis, Table of Contents Thromb Haemost 2008; 99(06): 1097-1103DOI: 10.1160/TH07-10-0634 New Technologies, Diagnostic Tools and Drugs Schattauer GmbH Accuracy of the CoaguChek XS for point-of-care international normalized ratio (INR) measurement in children requiring warfarin Authors Author Affiliations Mary E. Bauman 1 Stollery Children’s Hospital, University of Alberta, Edmonton, Alberta, Canada Karina L. Black 1 Stollery Children’s Hospital, University of Alberta, Edmonton, Alberta, Canada Mary P. Massicotte 1 Stollery Children’s Hospital, University of Alberta, Edmonton, Alberta, Canada Michelle L. Bauman 2 University of Alberta, Edmonton, Alberta, Canada Stefan Kuhle 3 School of Public Health, University of Alberta, Edmonton, Alberta, Canada Susan Howlett-Clyne 4 University of Alberta Hospital, Edmonton, Alberta, Canada George S. Cembrowski 4 University of Alberta Hospital, Edmonton, Alberta, Canada Laszlo Bajzar 2 University of Alberta, Edmonton, Alberta, Canada Recommend Article Abstract Buy Article(opens in new window) Summary Point-of-care INR (POC INR) meters can provide a safe and effective method for monitoring oral vitamin K antagonists (VKAs) in children. Stollery Children’s Hospital has a large POC INR meter loan program for children requiring oral VKAs. Our protocol requires that POC INR results be compared to the standard laboratory INR for each child on several consecutive tests to ensure accuracy of CoaguChek XS® (Roche Diagnostics, Basel Switzerland) meter. It was the objective of the study to determine the accuracy of the CoaguChek XS by comparing whole blood INR results from the CoaguChek XS to plasma INR results from the standard laboratory in children. POC INR meter validations were performed on plasma samples from two time points from 62 children receiving warfarin by drawing a venous blood sample for laboratory prothrombin (PT)-INR measurements and simultaneous INR determinations using the POC-INR meter. Agreement between CoaguChek XS INR and laboratory INR was assessed using Bland-Altman plots. Bland-Altman's 95% limits of agreement were 0.11 (-0.20; 0.42) and 0.13 (-0.22; 0.48) at the two time points, respectively. In conclusion, the CoaguChek XS meter appraisal generates an accurate and precise INR measure in children when compared to laboratory INR test results. Keywords KeywordsPoint-of-care - international normalized ratio - warfarin - home monitoring - child Full Text References References 1 Streif W, Andrew M, Marzinotto V. et al. Analysis of warfarin therapy in pediatric patients: A prospective cohort study of 319 patients. Blood 1999; 94: 3007-3014. 2 Andrew M, Marzinotto V, Brooker LA. et al. 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