Coagulation is routinely checked for bleeding disorders such as hemophilia; thrombophilia; diagnosis and staging of hypercoagulable state DIC; anticoagulant medication, during monitoring, and preoperatively. If a coagulation test is required, maintain a fast for at least 8-12 hours and refrain from strenuous physical activity and heavy labor for 24 hours; no smoking for half an hour in order to obtain accurate coagulation test results. The five coagulation tests are called the DIC series of five, which are the four coagulation tests plus the D-dimer test. The DIC is a screening test for coagulation, which includes prothrombin time (PT), activated partial thromboplastin time (APTT), and thromboplastin time (TT). fibrinogen and D-dimer are mainly used for screening the body’s ability to stop bleeding, and normal results indicate that the body can stop bleeding during injury or surgery without excessive blood loss. It is accompanied by activation of the fibrinolytic system. Therefore, the five coagulation tests are not disease-specific screening tests, but rather a screening test for hemostasis and activation of the fibrinolytic system.