The presence of anemia can be clarified by routine blood tests. If the hemoglobin is below the lower limit of normal, it indicates the presence of anemia. There are many causes of anemia. Once anemia occurs, the cause of anemia should be further clarified under the guidance of a doctor and treated accordingly. In addition, it should be combined with whether the patient has clinical manifestations, for example, patients with obvious anemia may show weakness, emaciation, loss of appetite, and pale skin mucosa. In particular, chest tightness and shortness of breath may appear after activity. Routine blood tests may reveal a significant decrease in hemoglobin and red blood cells, indicating the presence of anemia. In addition, the severity of anemia should be further evaluated based on the values of the corresponding indicators in the routine blood test, and corresponding tests should be performed, such as whether anemia is caused by loss of appetite or malnutrition. It is also necessary to consider whether there is a specific disease that causes excessive blood loss in the body, resulting in blood loss anemia, and to treat it accordingly according to the results of different tests.