Introduction of point-of-care testing in Japanese outpatient clinics is associated with improvement in time in therapeutic range in anticoagulant-treated patients.

Background: Warfarin reduces the risk of stroke in patients with atrial fibrillation, but requires a moderate-to-high time in therapeutic range (TTR). We hypothesized that point-of-care (POC) testing for prothrombin time-internationalized normalized ratio (PT-INR) could improve the TTR in patients receiving warfarin.

Methods And Results: Eight outpatient clinics that introduced POC testing for PT-INR participated in this study.