Nowadays, people are paying more and more attention to their health, and many units and even individuals will organize health check-ups every year. Routine blood, urine, biochemical indicators and even blood viscosity have become regular mandatory tests. But there is an easy and important test that is overlooked, it is the “blood sedimentation”. The full name of hematocrit is erythrocyte sedimentation rate, and we often use the abbreviation ESR to express it. It refers to the rate of sedimentation of red blood cells under certain conditions. The hematocrit test is very simple, requiring only 2 ml of anticoagulated blood, without fasting, and costs only a few dollars, but it is important in some pathological situations. At present, the main method of blood sedimentation measurement implemented in China is the Weiss method, and the normal range of values differs slightly by gender. In men, 0-15mm/1 hour is normal, while in women, 0-20mm/1 hour is normal. The speed of blood sedimentation is influenced by many factors. In clinical practice, we often use the blood sedimentation to reflect the inflammatory condition of the body, the extent of the disease, and the effectiveness of treatment. In addition, elevated sedimentation can sometimes indicate the presence of certain diseases. The common clinical diseases with increased sedimentation are: 1) various infectious inflammatory diseases, such as tuberculosis, bacterial or viral microbial infections; 2) rheumatic diseases, such as rheumatoid arthritis, systemic lupus erythematosus, rheumatic polymyalgia, etc.; 3) blood diseases, such as severe anemia, macroglobulinemia, multiple myeloma, etc.; 4) malignant tumors, tissue damage, etc. However, it is worth noting that blood sedimentation increases slightly in women during menstruation and pregnancy, and that blood sedimentation is often higher than the normal range in elderly people over 60 years old. These are normal, and the values are not too high. Slowed sedimentation is generally of little significance and is mainly seen in dehydrated hemoconcentration, true erythrocytosis and diffuse intravascular coagulation due to various causes. As you can see, the hematocrit test is very important to give us the necessary hints to be aware of the disease before it is fully manifested. If you have recently had unexplained fever, weight loss, night sweats, joint pain, etc., it is recommended that you go to the hospital to have your blood sedimentation checked so that your doctor can narrow down the scope of your diagnosis. In addition, a blood sedimentation test during a health check-up will also detect potential diseases early.