Bleeding time is a test used to determine how quickly your blood clots to stop you from bleeding. The test is a basic assessment of how well your blood platelets work to form clots. The test helps identify people who have defects in their platelet function. This is the ability of blood to clot following a wound or trauma. Normally, platelets interact with the walls of blood vessels to cause a blood clot. There are many factors in the clotting mechanism, and they are initiated by platelets. The bleeding time test is usually used on patients who have a history of prolonged bleeding after cuts, or who have a family history of bleeding disorders. Also, the bleeding time test is sometimes performed as a preoperative test to determine a patient's likely bleeding response during and after surgery. However, in patients with no history of bleeding problems, or who are not taking anti-inflammatory drugs, the bleeding time test is not usually necessary. Clotting tests (CT) are used to diagnose and assess bleeding problems. This simple test has been used to diagnose hemophilia, but it does not detect mild coagulation disorders. Its chief application is in monitoring anticoagulant therapy. It is rarely used in clinical practice. Also called coagulation time.