When measuring body temperature, which method is least accurate?

The axillary method is considered the least accurate for measuring body temperature. This method involves placing the thermometer in the armpit, which can lead to variations in the readings due to factors such as ambient temperature and how well the arm is positioned against the body. Body heat can escape through the skin in the underarm area, resulting in a cooler and often less precise measurement compared to internal methods, such as rectal or oral, or even aural measurements taken from the ear.

In contrast, the rectal method provides a core body temperature reading, making it one of the most accurate options. The oral method can also yield reliable results when conducted correctly, while the aural method, which measures temperature through the ear, efficiently captures the temperature of the blood flowing through the ear drum, providing another accurate approach. The variability and external influences affecting axillary measurements contribute to its ranking as the least reliable method for assessing body temperature.