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Biological variation in tests of hemostasis.
Giuseppe Banfi1, Massimo Del Fabbro
1IRCCS Galeazzi, Milano, Italy. Banfi1@unimi.it
Seminars in Thrombosis and Hemostasis
|December 17, 2008
Summary
Understanding biological variation in hemostasis tests is key. Low variability in coagulation tests contrasts with high variability in fibrinolysis, impacting clinical interpretation and preoperative screening.
Area of Science:
- Clinical Biochemistry
- Hematology
- Laboratory Medicine
Background:
- Biological variability comprises interindividual and intraindividual components.
- Analysis of biological variation is essential for defining critical differences in laboratory results.
- Existing data on hemostasis test biological variation are outdated.
Purpose of the Study:
- To update and confirm biological variation data for hemostasis tests using modern automated methods.
- To assess the impact of biological variation on preoperative coagulation screening.
- To provide updated reference ranges for interpreting hemostasis parameters.
Main Methods:
- Utilized modern, fully automated analytical platforms.
- Quantified interindividual and intraindividual variability for various hemostasis parameters.
- Calculated the index of individuality to assess the influence of different variability components.
Main Results:
- Coagulation screening tests (prothrombin time, activated partial thromboplastin time) exhibit low biological variation.
- Thrombin time demonstrates very low within- and between-subject variability.
- Fibrinolytic parameters (PAI-1, fibrinopeptide A) show high biological variability.
- Index of individuality indicates preoperative screening is influenced by interindividual variability.
Conclusions:
- Updated biological variation data for hemostasis tests are now available.
- High variability in fibrinolytic parameters necessitates careful clinical interpretation.
- Interindividual variability significantly influences preoperative coagulation screening outcomes.
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