Because the internal structure of the electronic sphygmomanometer is more complex, the working principle is also more complex, so the electronic sphygmomanometer can not be calibrated by themselves, must go to a professional testing center calibration or at the purchase, the manufacturer calibration. Sphygmomanometer needs to be calibrated, and to be calibrated by regular methods to ensure the accuracy of the test results, always pay attention to the test results of the sphygmomanometer, and regularly take it to the aftermarket calibration. If the electronic sphygmomanometer appears inaccurate values, you can use the electronic sphygmomanometer in the forearm for blood pressure detection, with the mercury column sphygmomanometer in the same position for measurement, by repeated measurement of the electronic sphygmomanometer in different times, you can decide the range according to the stability of the electronic sphygmomanometer and test degree, the premise is that you need to understand your blood pressure, after 4-5 times of testing will have 2 values, on the measurement accurate.