Standardization of β-Thromboglobulin and Platelet Factor 4: A Collaborative Study to Investigate the Sources and Extent of Variation in the Measurement of Platelet Specific Proteins

Summary

A collaborative study involving seven laboratories has been carried out to investigate the sources and extent of variation in the measurement by radioimmunoassay of β-thromboglobulin (β-TG) and platelet factor 4 (PF4). Three plasma samples, one purified β-TG sample and two purified PF4 samples were assayed against house standards for the respective antigens by each laboratory.

The main source of variation of both β-TG and PF4 measurements was inter-assay (particularly for PF4). It was found that a significant component of this variation was due to the participants’ use of different preparations as house standards for β-TG and for PF4. This indicates that the first step in the standardization of β-TG and PF4 measurement should be the introduction of a reference for each.

Keywords

Collaborative study - Radioimmunoassay - β-thromboglobulin - Platelet factor 4

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