Coagulation tests: First, they can assist in the diagnosis of many diseases, such as hemophilia and DIC. Second, it can assist in the treatment of many diseases, such as anticoagulation therapy for cardiovascular and cerebrovascular diseases. In clinical practice, the eight items of coagulation are mainly examined, including coagulation time, prothrombin time, prothrombin time, partially activated prothrombin time, fibrinogen, D-dimer, prothrombin time ratio, and prothrombin activity. The eight items of coagulation examination enable a comprehensive examination of the function of endogenous coagulation pathways and exogenous coagulation pathways. If a patient has coagulation problems, it can be determined whether there is a problem with the endogenous pathway or the exogenous pathway. Problems with the endogenous pathway are mostly seen in hemophilia, and can also guide cardiovascular and cerebrovascular diseases, the application of anticoagulant drugs such as warfarin, and can also provide an effective reference for the diagnosis of various coagulation disorders.