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.