Long-Term Stability Studies on the WHO IRP for Thromboplastin (Human Plain BCT/253)

Summary

Long-term stability studies on the WHO second primary International Reference Preparation (IRP) for thromboplastin (human plain BCT/253) stored at ™20° C have been conducted for ten years.

Three centres took part in the exercise using frozen normal and coumarinised plasma samples which were tested throughout. There has been no measurable change in the prothrombin time performance of the human plain IRP over the ten-year period. It can therefore be concluded that new IRP may continue to be calibrated against this preparation in accord with WHO recommendations.

• References

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• 2 Thomson JM, Tomenson JA, Poller L. The calibration of the second primary international reference preparation for thromboplastin (Thromboplastin, Human Plain, Coded BCT/253). Thromb Haemost 1984; 52 (03) 336-342
• 3 WHO Expert Committee on Biological Standardisation 1984. 34th Report. WHO Technical Report Series 700.19.