The prothrombin time (PT) test measures how quickly blood clots. The partial thromboplastin time (PTT) is mainly used to monitor a person's response to anticoagulant therapies. The international normalized ratio (INR) calculation helps ensure that PT test results are standardized and accurate.
What does PT and PTT tell you?
Definition. Partial thromboplastin time (PTT) is a blood test that looks at how long it takes for blood to clot. It can help tell if you have a bleeding problem or if your blood does not clot properly. A related blood test is prothrombin time (PT) .
What's the difference between PTT and aPTT?
Description. Partial thromboplastin time (PTT) and activated partial thromboplastin time (aPTT) are used to test for the same functions; however, in aPTT, an activator is added that speeds up the clotting time and results in a narrower reference range.
What is the difference between PTT and PT INR?
The prothrombin time (PT) w/INR test measures the length of time it takes for a blood clot to form in a sample of blood. A partial Thromboplastin Time (PTT) test is ordered when someone has unexplained bleeding or clotting.