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The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well

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Prothrombin time and partial thromboplastin time assay considerations.

¹Department of Laboratory Medicine, School of Medicine, University of California San Francisco, San Francisco, CA, USA. vang@acmedctr.org

Clinics in Laboratory Medicine

|August 12, 2009

Summary

This summary is machine-generated.

Understanding laboratory coagulation testing is crucial for interpreting study results. This review covers factors affecting prothrombin time (PT) and activated partial thromboplastin time (aPTT) for accurate clinical application.

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Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

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Published on: September 9, 2012

Area of Science:

Clinical Biochemistry
Hematology
Laboratory Medicine

Background:

Prothrombin time (PT) and activated partial thromboplastin time (aPTT) are established global assays for assessing hemostasis.
Accurate interpretation of coagulation studies is vital for clinical decision-making.
Numerous pre-analytical and analytical variables can impact PT and aPTT results.

Purpose of the Study:

To review critical laboratory issues and variables influencing PT and aPTT.
To enhance the reader's awareness of potential confounders in coagulation testing.
To provide a foundation for critically evaluating research relying on these hemostatic assays.

Main Methods:

Literature review of factors affecting coagulation assays.
Analysis of known variables impacting PT and aPTT.
Discussion of the International Normalized Ratio (INR) calculation.

Main Results:

Identified key laboratory variables that influence PT and aPTT.
Highlighted the importance of standardized testing procedures.
Emphasized the impact of these variables on the reliability of published data.

Conclusions:

Awareness of laboratory variables is essential for accurate interpretation of PT and aPTT.
Critical evaluation of published studies requires understanding potential testing interferences.
Standardization and careful consideration of influencing factors improve the clinical utility of coagulation tests.