Medical research hasn’t determined an exact correlation between oral, rectal, ear, armpit, and forehead temperature measurements. Generally, the correlation of temperature results are as follows:
- The average normal oral temperature is 98.6°F (37°C).
- A rectal temperature is 0.5°F (0.3°C) to 1°F (0.6°C) higher than an oral temperature.
- An ear (tympanic) temperature is 0.5°F (0.3°C) to 1°F (0.6°C) higher than an oral temperature.
- An armpit (axillary) temperature is usually 0.5°F (0.3°C) to 1°F (0.6°C) lower than an oral temperature.
- A forehead (temporal) scanner is usually 0.5°F (0.3°C) to 1°F (0.6°C) lower than an oral temperature.
Information Sources: https://www.mottchildren.org/health-library/tw9223
The reference body site of PT3 is oral. Please compare with oral temperature from the testing result. Ear and rectal temperatures are normally higher than oral and forehead temperatures.
When people develop a fever, the heat conduction will take time to arrive at the forehead, there is a time gap. Suggest measuring every 5 minutes until the temperature stabilizes.
*credit to Sylvain of iHealth Labs EU
https://helpcenter.ihealthlabs.eu/hc/en-gb/articles/360007212377-iHealth-PT3-Why-my-test-results-are-lower-than-the-temperature-tested-from-other-body-sites-