International Normalized Ratio (INR): Performance of External Quality Assessment 2016 results - PNAEQ and ECAT Foundation

The International Normalized Ration (INR) is derived from the measurement of the Prothrombin Time (PT) and the International Sensitivity Index (ISI), and is a quantitative measure of the responsiveness of individual thromboplastin reagents to the different clotting factors involved in the PT measurement. Under the INR system, all results are standardized. For example, a person taking an oral anticoagulant (ex. Coumadin) would need regularly to have a blood test to measure the INR. The INR permits patients on anticoagulants to travel and obtain comparable test results wherever they are. So it is very important to verify the laboratories performance over this test. In 2014 the Portuguese National External Quality Assessment Program (PNAEQ) has established a consortium with ECAT Foundation for INR measurement where Portuguese laboratories are included in the statistical analysis. The main objective of this study was to evaluate the performance for INR of PNAEQ participants that used two different thromboplastin reagents during 2016 and compared those with the results of ECAT participants.

Keywords

Avaliação Externa da Qualidade AEQ Programa Nacional de Avaliação Externa da Qualidade PNAEQ Portuguese National External Quality Assessment Program INR International Normalized Ration