Methods of Measurement Body Temperature

Taking a patient's temperature is an initial part of a full clinical examination. Sites used for measurement include:

• In the anus (rectal temperature)
• In the mouth (oral temperature)
• Under the arm (axillary temperature)
• In the ear (tympanic temperature)
• In the vagina (vaginal temperature)
• On the skin of the forehead
• Over the temporal artery
• In the gut (by swallowing a small thermometer)

The temperature reading depends on which part of the body is being measured. The typical daytime temperatures among healthy adults are as follows:

• Temperature in the anus (rectum/rectal), vagina, or in the ear (otic) is about 37.6 °C (99.7 °F)
• Temperature in the mouth (oral) is about 36.8 °C (98.2 °F)
• Temperature under the arm (axillary) is about 36.4 °C (97.6 °F)
  

Normal human body temperature varies slightly from person to person and by the time of day. Consequently, each type of measurement has a range of normal temperatures. The range for normal human body temperatures, taken orally, is 36.8±0.7 °C (98.2±1.3 °F).[1] This means that any oral temperature between 36.1 and 37.5 °C (96.9 and 99.5 °F) is likely to be normal.

The temporal artery is close to the surface of the skin and therefore accessible for reading. The temporal artery is linked to the heart by the carotid artery which is directly linked to the aorta. It forms part of the main trunk of the arterial system. So long as the patient’s blood flow is permanent and regular, the method allows precise measurement of the temperature.

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