The laboratory tests for anemia are as follows: First, the number of red blood cells, the number of red blood cells in anemic patients is lower than normal, there are exceptions, that is, when iron deficiency anemia, although anemic, the number of red blood cells is not necessarily lower than normal. Red blood cell pressure, in all anemic patients, the red blood cell pressure is lower than normal. The hemoglobin concentration is lower than normal in all anemic patients, and the more severe the anemia, the lower the hemoglobin concentration. Below 60g/L is severe anemia and below 30g/L is very severe anemia. The average volume of red blood cells is reduced, which is a small-cell anemia, common in iron deficiency anemia and thalassemia. V. Hemoglobin volume, anemia with reduced average hemoglobin volume is small cell hypochromic anemia. If the average hemoglobin amount is increased, this type of anemia is megaloblastic anemia.