INR is a standardized way of expressing PT results, ensuring consistency across different laboratories and testing methods. It’s commonly used to monitor patients on oral anticoagulant therapy, such as warfarin, to ensure they are within the therapeutic range and at a reduced risk of bleeding or clotting.

Fibrinogen is a protein essential for blood clot formation. Measuring fibrinogen levels helps diagnose bleeding disorders, liver disease, and conditions that affect fibrinogen levels, such as disseminated intravascular coagulation (DIC).

TT measures the time it takes for a clot to form after thrombin is added to the blood sample. It helps evaluate the final step of the coagulation process and can detect abnormalities in fibrinogen function or the presence of inhibitors.

APTT measures the time it takes for your blood to clot after adding a substance that triggers the intrinsic coagulation pathway. It helps evaluate the function of factors VIII, IX, XI, and XII, as well as the effectiveness of heparin therapy and diagnose certain bleeding disorders.