Prothrombin Time Standardization Report of the Expert Panel on Oral Anticoagulant Control: A Minority Opinion

Summary

The ICTH/ICSH collaborative study failed to achieve its aims because each combination of plasma, thromboplastin and method was tested by too few laboratories in relation to intra and inter laboratory variation, and because the stability of the reference thromboplastin 70/178 is suspect. The evidence of the study does not support the superiority of reference thromboplastins over reference plasmas, but the concept of reference plasma was not adequately explored.

• References

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