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Thromb Haemost 2002; 88(06): 992-995
DOI: 10.1055/s-0037-1613345
Involvement of Thrombin Receptors in the Subject-dependent Variability in Ca2+ Signal Generation
Schattauer GmbH

European Concerted Action on Anticoagulation (ECAA): International Normalized Ratio Variability of CoaguChek and TAS Point-of-Care Testing Whole Blood Prothrombin Time Monitors

L. Poller   *
1   ECAA Central Facility, School of Biological Sciences, The University of Manchester, Manchester, UK
,
M. Keown
1   ECAA Central Facility, School of Biological Sciences, The University of Manchester, Manchester, UK
,
N. Chauhan
1   ECAA Central Facility, School of Biological Sciences, The University of Manchester, Manchester, UK
,
C. Shiach   *
2   Department of Haematology, Manchester Royal Infirmary, Oxford Road, Manchester, UK
,
A. M. H. P. van den Besselaar   *
3   Haemostasis and Thrombosis Research Centre, Leiden University Medical Center, Leiden, The Netherlands
,
A. Tripodi   *
4   A Bianchi Bonomi, Haemophilia and Thrombosis Centre, IRCCS Maggiore Hospital, University of Milan, Milan, Italy
,
J. Jespersen   *
5   Department for Thrombosis Research, University of Southern Denmark and Department of Clinical Biochemistry, Ribe County Hospital, Esbjerg, Denmark
› Author Affiliations
Further Information

Publication History

Received 22 May 2002

Accepted after revision 19 August 2002

Publication Date:
09 December 2017 (online)

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Summary

The object was to assess the variability in displayed International Normalised Ratio (INR) between monitors of the same manufacture using whole blood samples from the same subjects. Two brands of monitor, CoaguChek Mini and the TAS PT-NC were tested.

14 instruments of each brand were tested on the same day at the same laboratory by the same operator using identical blood samples to avoid between-centre differences in samples and operator technique. Whole blood samples from two normal donors and four coumarintreated patients were tested to assess between-instrument variability of INR.

Results have been coded. There was a much wider dispersion of INR on Brand B than on Brand A. One Brand A instrument failed to give a result with one of the two whole blood samples from one patient. One Brand B monitor gave an aberrant result with one of the samples from a normal subject.

On both brands of monitor, INR variability appeared to be due mainly to duplication differences rather than between-instrument variability on both normal and coumarin whole blood samples.

Keywords

POCT monitors - prothrombin time - International Normalised Ratio - between-instrument variability - within-instrument variability

* ECAA Steering Group Members


 

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