Normal measurement of underarm temperature, generally requires a measurement time of 5-10 minutes, should not be too short, nor too long. Thermometer reflects the human body temperature, mainly through the conduction of heat conduction of the body’s temperature on the thermometer, to achieve a temperature balance, so as to reflect the body’s true body temperature. The general measurement of 5-10 minutes is possible, no need to entangle is 5 minutes or 10 minutes. In addition, clinical measurement of body temperature should be careful to dump the thermometer to below 35 ℃, to close contact between the head of the thermometer and the armpit, do not leave a gap, and do not clip a foreign body, so as not to affect the accuracy of the measurement. Too short a measurement time may lead to inaccurate measurement and low values affect the true judgment effect; too long a measurement time may cause relative fluctuations in body temperature, which does not reflect the body’s temperature at that time within the established time. In addition, when taking readings, be sure to look at it flat, so as not to cause visual bias and thus affect the results.