Thromb Haemost 1986; 55(03): 379-382
DOI: 10.1055/s-0038-1661568
Original Article
Schattauer GmbH Stuttgart

Calibration of BCT/441, the ICSH Reference Preparation for Thromboplastin

Jean M Thomson
The UK Reference Laboratory for Anticoagulant Reagents and Control, Withington Hospital, Manchester, UK
,
K V Darby
The UK Reference Laboratory for Anticoagulant Reagents and Control, Withington Hospital, Manchester, UK
,
L Poller
The UK Reference Laboratory for Anticoagulant Reagents and Control, Withington Hospital, Manchester, UK
› Author Affiliations
Further Information

Publication History

Received 04 November 1985

Accepted 14 April 1986

Publication Date:
18 July 2018 (online)

Summary

An international collaborative exercise has been undertaken to calibrate a secondary international reference preparation (IRP) of thromboplastin on behalf of the International Committee for Standardization in Haematology (ICSH). This preparation of British Comparative Thromboplastin (BCT/441) is required because supplies of the WHO primary IRP (BCT/253) are necessarily limited.

The calibration was performed at seven centres with only a small degree of interlaboratory variation. As a result of this study an ISI value of 1.04 has been assigned to the preparation.

Opportunity was also taken to assess the reliability of a simplified calibration based on lyophilised plasmas. The results of the latter appeared reliable.

BCT/441 will be available to officially designated National Control Laboratories for calibration of local thromboplastins to promote prothrombin time standardization in oral anticoagulant control.

 
  • References

  • 1 WHO Expert Committee on Biological Standardization. 33rd Report WHO Technical Report Series 1983 687. 81-105
  • 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 Haemostas 1984; 52: 336-342
  • 3 Loeliger EA, van den Besselaar AM H P, Hermans J, van der Velde EA. Certification of three reference materials for thromboplastins. BCR Information. Commission of the European Communities, Brussels 1981
  • 4 Tomenson JA, Thomson JM. Standardization of the prothrombin time. In: Blood Coagulation and Haemostasis Thomson JM. (ed.) pp 370-409 Churchill Livingstone; Edinburgh: 1985
  • 5 Van der Velde EA. Orthogonal regression equation. In: Thromboplastin Calibration and Oral Anticoagulant Control Van den Besselaar AM H P, Gralnick HR, Lewis SM. (eds.) pp 25-40 Martinus Nijhoff; Boston: 1984
  • 6 Tomenson JA. A statistician’s independent evaluation. In: Thromboplastin Calibration and Oral Anticoagulant Control Van den Besselaar AM H P, Gralnick HR, Lewis SM. (eds.) pp 87-108 Martinus Nijhoff; Boston: 1984
  • 7 Recommended methodology for using WHO International Reference Preparations for Thromboplastin. WHO Geneva
  • 8 Kirkwood TB L. Calibration of reference thromboplastins and standardization of the prothrombin time ratio. Thromb Haemostas 1983; 49: 238-244