Prothrombin Time (PT), aka Protime or Pro Time: Measures how long it takes for a clot to form in a sample of blood. Since PT evaluates the ability of blood to clot properly, it can be used to help diagnose bleeding. When used in this instance, it is often used to evaluate the function of all coagulation factors. A prolonged, or increased, PT means that your blood is taking too long to form a clot. Normal range is 8.7-11.5
International Normalization Ratio (INR): A system established by the World Health Organization (WHO) and the International Committee on Thrombosis and Hemostasis. INR is the ratio between the coagulation time of a sample of blood and the normal coagulation time, when coagulation takes place in certain standardized conditions. All results are standardized using the international sensitivity index for the particular thromboplastin reagent and instrument combination utilized to perform the test. Normal range is 0.8-1.2