Adoption and validation of the international normalized ratio for monitoring oral anticoagulant therapy: the situation in 1989.
The INR/ISI system has been validated in multicenter trials. The system provides a reliable scale for the intensity of oral anticoagulation. It has been recognized that the ISI is slightly dependent on the instrument used for prothrombin time determination. External quality assessment (EQA) of the INR in national programs should be stimulated. EQA results suggest that the precision of the INR can be improved. Many physicians prescribing coumarin congeners are not familiar with the INR system. Improvement of the situation can only be achieved by continuous education.
Department of Haematology, University Hospital, Leiden.
A M
AM
van den Besselaar
D000284:Administration, Oral; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007394:International System of Units; D015337:Multicenter Studies as Topic; D011517:Prothrombin Time; D011786:Quality Control; D012015:Reference Standards; D013925:Thromboplastin / Q000592:standards
D000925:Anticoagulants; D013925:Thromboplastin