Quality assessment in point-of-care coagulation testing.

Point-of-care (POC) testing in the field of hemostasis is rapidly expanding in many countries. This includes use of global tests of hemostasis in operating theaters and especially use of POC monitors for determination of the international normalized ratio (INR) for monitoring oral anticoagulant therapy. Issues related to internal quality control and external quality assessment for these devices are reviewed. Data from external quality assessment exercises involving users of several different POC-INR devices is described, and use of split samples where a patient sample is analyzed by both a POC device and by a conventional laboratory method is described.