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PubMed · 7974635

Assessing random error in the international normalized ratio.

J F Inciardi
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Abstract

Changes in the international normalized ratio (INR) following warfarin administration may be explained not only by the attendant anticoagulant effect but also, in part, by random errors normally associated with laboratory assays. Thus, a patient's true INR will differ from the reported value by some random error related to the variability in the prothrombin time (PT) assay. By employing a statistical technique known as the delta method, the error expected in an INR for a particular institution can be estimated by taking the product of the international sensitivity index (ISI) and the coefficient of variation (CV) for the PT assay.

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Drug MonitoringHumansProthrombin TimeWarfarinJournal Article

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J F Inciardi. 1994. Assessing random error in the international normalized ratio.. https://doi.org/10.1097/00007691-199408000-00015

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