Which temperature measurement method is considered the most accurate for adults?

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

Answer: (C)

Rectal temperature measurement is considered the most accurate for adults because it reflects the core body temperature more reliably than other methods. The rectum is well-vascularized and has less variation in temperature due to external influences, making it a stable indicator of the internal body temperature. It is also less susceptible to environmental factors and is not influenced by factors like eating, drinking, or breathing, which can affect oral temperature readings.

In contrast, oral temperature can be affected by recent food or beverage intake, making it less reliable immediately after eating or drinking. Axillary measurements are often less precise because they measure temperature over skin rather than core body temperature, which can lead to underestimations. Tympanic measurements, while quick and convenient, can be influenced by factors like earwax or improper placement, which can compromise their accuracy. Thus, rectal temperature measurement is the preferred method when an accurate assessment of core body temperature is required in adults.