Which body temperature reading method is likely to be the least accurate?

• A. Oral
• B. Rectal
• C. Axillary
• D. Ear

Answer: (C)

The axillary method for measuring body temperature is considered to be the least accurate among the common techniques. This is primarily because the temperature taken from the armpit is influenced by multiple factors, such as ambient temperature, skin temperature, and the duration of time the thermometer is placed in the axilla. As a result, the readings tend to be lower than the actual internal body temperature.

In contrast, rectal temperatures are typically the most accurate, as they reflect core body temperature. Oral temperatures can also be reliable when taken properly, while ear (tympanic) thermometers offer a quick and mostly reliable measurement as they measure the infrared heat from the eardrum, closely correlating to core body temperature. Hence, while the axillary method is easy to perform, its susceptibility to external factors makes it less reliable compared to the other methods.