Letter from the Director: Prothrombin Time Tests & Blood Clotting

Originally published in LabTalk (Volume 3, Issue 3, 2008), the quarterly newsletter of Aculabs. Prothrombin time (PT) tests measure clotting time in a blood sample from the activation of factor VII through the formation of fibrin clot. PT evaluates the integrity of the extrinsic and common pathways of coagulation. It is measured in seconds and