ABSTRACT
The pattern of tests employed and technologies developed within hemostasis laboratories
has changed considerably within the last 10 years. These changes have presented challenges
to external quality assessment (EQA) providers, including the United Kingdom National
External Quality Assessment Scheme (NEQAS). EQA for point-of-care devices used for
monitoring oral anticoagulant therapy has focused on provision of suitable material
to assess performance of devices designed for capillary blood testing, and on education
of a user group not usually trained in laboratory quality control procedures. Development
of novel therapeutic agents for hemophilia has presented challenges regarding standardization
of assays for monitoring treatment, whereas advances related to laboratory testing
and automation have not always been accompanied by improved accuracy and precision.
EQA provision has also been shown to be of value in molecular genetic screening tests
for thrombophilia, and in highlighting standardization issues related to D-dimer measurement
in the exclusion of deep vein thrombosis. The increasing prevalence of screening tests
of global hemostasis, such as thrombin generation tests and thromboelastography, presents
additional challenges to EQA providers in the attempt to standardize these new and
potentially beneficial technologies.
KEYWORDS
External quality assessment - point-of-care testing - hemophilia - D-dimer
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Dr. I. Jennings
UK NEQAS for Blood Coagulation, Rutledge Mews
3 Southbourne Road, Sheffield S10 2QN, United Kingdom
Email: i.jennings@coageqa.org.uk