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Regular multilaboratory surveys of laboratories by the Royal College of Pathologists of Australasia Quality Assurance Program (QAP) have been conducted to assess proficiency in tests of hemostasis for the last 40 years. This article focuses primarily on specialized assays of hemostasis, for which surveys have been conducted for some 10 years. For von Willebrand disease (vWD) evaluations, a total of 47 plasma samples have been dispatched to survey participants, including representative samples from normal individuals plus all of the major vWD subtypes (i.e., types 1, 2A, 2B, 2M, 2N, and 3). These surveys have focused partly on the issue of diagnostic interpretive error rates associated with different assays and test panels. In this context, considerable improvement is seen when laboratories incorporate the vWF:collagen-binding assay into the test panel. Thrombophilia-associated tests assessed by the program and discussed in this review include activated protein c resistance, lupus anticoagulant, and deficiencies of protein C, protein S, and antithrombin. Other tests briefly reviewed here include factor assays and inhibitors, D-dimer, and heparin/anti-Xa assays. Anticardiolipin antibody and anti-beta(2)-glycoprotein I antibody (aB(2)GPI) testing, assessed by the Immunology QAP, is also reviewed briefly, as are genetic tests associated with thrombophilic markers such as factor V Leiden and the prothrombin gene.

There are many benefits to the overall process of standardization for tests of hemostasis and thrombosis. Nevertheless, it should also be recognized there are several specific problems and limitations to this process, as highlighted in this review. Some of the issues are formidable, but it is hoped that they are not insurmountable. Sometimes, clinical pressures drive diagnostic test processes before they are formally proven to be of clinical value. Such clinical pressures drive diagnostic changes in the hemostasis laboratory, including the incorporation of new and emerging technologies, which in turn drives the need for evolving and effective external quality assurance. Incorporated into the diagnostic or test-performance process are a large number of organizations involved in driving standardization, with the ultimate intention of improving diagnostics, but this process will also have unintended potential for adverse outcomes. Although this review notes many of the benefits to the process, it focuses primarily on those negative factors that are often less obvious but still require attention and process review.