RBC refers to red blood cells, and a high coefficient of variation of red blood cell distribution width often indicates that the red blood cells are not homogeneous, which should be determined by referring to the average red blood cell volume and other indicators. The coefficient of variation of RBC distribution width is the coefficient of variation of red blood cell volume size, which is important for the diagnosis of anemia. The normal range is 11.5%-14.5%, and this high value suggests that the volume size of red blood cells varies greatly. When the coefficient of variation of RBC distribution width is high, it should be combined with other test results, such as hemoglobin and average red blood cell volume. In patients with anemia, there are several situations in which the coefficient of variation of RBC distribution width is high: the average red blood cell volume is normal, suggesting aplastic anemia, PNH, G6PD deficiency and other diseases, and the treatment is based on immunosuppression, and some serious patients need hematopoietic stem cell transplantation. Increased average red blood cell volume, suggesting megaloblastic anemia, MDS, etc., and treatment should be supplemented with folic acid and vitamin B12. Decreased average red blood cell volume suggests iron deficiency anemia, and iron supplementation is the mainstay of treatment. If the coefficient of variation of RBC distribution width is high, you should consult a doctor in time for further diagnosis and formulation of individualized diagnosis and treatment plan to avoid delaying your condition.