The most feared indicators of blood routine are: red blood cell count, hemoglobin concentration, white blood cell count, and platelet count. Red blood cell reference value: (4.0~5.5)×10¹²/L (male), (3.5~5.0)×10¹²/L (female); hemoglobin reference value: 120~160g/L (male), 110~150g/L (female); white blood cell reference value: (4~10)×10⁹/L; platelet reference value: (100~300 ) × 10⁹/L. 1. Abnormal red blood cell count and hemoglobin concentration: relative increase is seen in severe dehydration, severe burns, uremia, etc. Absolute increase is seen in erythrocytosis; physiological decrease is seen in the elderly or pregnant women, and pathological decrease is seen in anemia, leukemia, etc. 2. Abnormal white blood cell count: leukocytosis can be seen in infection, trauma, poisoning, tumor, hemorrhage, leukemia, etc.; leukopenia can be seen in infection, aplastic anemia, radiotherapy or chemotherapy, systemic lupus erythematosus. 3. Abnormal platelet count: increase in acute infections, myeloproliferative tumors, acute hemolysis, etc.; decrease in disseminated intravascular coagulation, immune thrombocytopenia, lymphoma, splenomegaly, etc.. If there is any abnormality in blood routine, it is recommended to consult a professional doctor to clarify the cause of the disease.