Generally the more common reasons that can affect the blood glucose measurement are: 1. Some patients, when measuring blood glucose, because the bleeding is not deep and the bleeding is small, so they force to squeeze, and as a result, the tissue fluid is also squeezed out, the sugar concentration in the tissue fluid is generally lower than that of the plasma, too much tissue fluid will dilute the specimen and affect the accuracy of the measurement. In addition, the finger should have a certain temperature, if the temperature is very low, blood vessels are prone to contraction, resulting in too little bleeding, the results will also be inaccurate. 2. Patients with blood who use iodine for local disinfection and measure without waiting for the disinfectant to dry completely will likewise dilute the specimen, leading to deviations in the test results. Therefore, it is recommended that patients disinfect with more volatile alcohol, and also wait for the alcohol to evaporate completely before testing, on the one hand, alcohol dilutes the blood, on the other hand, the residual alcohol will interfere with the test paper oxidase, and the results will also be inaccurate. 3, to pay attention to the expiration date of the test paper. Some test paper is bare in a whole box, take out a test paper to immediately cover the box tightly, keep the test paper dry to prevent its oxidation reaction. 4, there are also some special circumstances, such as inadvertently dropped the blood glucose meter (how much you guys hate to measure blood glucose ah), may cause the machine itself error, need to recalibrate. And also pay attention to the maintenance of the blood glucose meter, usually the storage temperature of the instrument should be between -40 ℃ – +70 ℃, the relative humidity should be below 85%. Avoid storing the blood glucose meter near electromagnetic fields (such as cell phones, microwave ovens, etc.). If the blood glucose meter used is a drip blood glucose meter, it is generally accurate within two years, and after two years, patients are recommended to go to the after-sales service maintenance station to do a calibration and bald head maintenance. 5, clinically, the blood glucose results measured by blood glucose meter are high in anemic patients, and will be low in erythrocytosis, dehydration or plateau areas; patients’ excessive psychological tension will make blood glucose rise; patients’ use of certain drugs will have an impact on the measurement results, such as a large amount of vitamin C, glutathione, etc., which will make the results low; the use of glucose during intravenous drip will make the results high, and this point is sometimes overlooked in the clinic; a large amount of Infusion will dilute the blood, which will also affect the measurement result. To introduce some correct methods and tips for blood glucose measurement: 1. The correct blood collection method is to choose the thin skin on both sides of the ring finger tip, because the blood vessels on both sides of the finger are rich and the nerve endings are less distributed. In this part of the blood collection is not only painless, and the blood volume is sufficient. The blood collection pen should be close to the skin, the hand must be steady and accurate, so as not to suffer a second time, after the needle prick, quickly wipe off the small amount of blood spilled with a dry cotton swab, and then gently push both sides of the finger, so that the blood slowly overflow can be. 2, in addition to the patient’s arm down for 15 seconds, the other hand from the wrist down the stroke, or shake hands, rub hands for about half a minute, can make the fingertips of the peripheral vessels filled, to facilitate blood collection. 3, elderly diabetic patients with poor peripheral circulation, if the above methods do not work, you can also use hot water to soak hands. Have your family prepare a basin of warm water at 40 degrees Celsius, and soak your fingers for 5 minutes. As the temperature of the hand rises, blood circulation is accelerated, blood vessels expand, and blood can be collected.