Doctors commonly used mercury sphygmomanometer, the measurement principle is the auscultation method, that is, through the stethoscope with the mercury sphygmomanometer, through the sound as well as changes in the column of mercury to determine the level of blood pressure, also known as the gold standard of blood pressure measurements, it can be said that the principle of measurement of the mercury sphygmomanometer itself is the most accurate.
The electronic sphygmomanometer is mostly based on the oscillometric method, in the measurement principle, compared to the mercury sphygmomanometer has a certain deviation, but through the computer algorithm regulation, as well as the optimization of the measurement data, the error can be controlled in a very small range, from the medical point of view, the error is acceptable, and will not affect the measurement results of the judgement, the reliability of the high degree.