Which temperature site is generally considered least accurate for core body temperature?

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

Answer: (C)

Axillary temperature is the least reliable for reflecting core body temperature because it measures skin temperature in the armpit, which is highly influenced by the surrounding environment, air flow, sweat, and how snugly the arm is held against the body. This peripheral reading tends to be lower than core temperature—typically about 0.5–1.0°C lower—so it can miss fevers or misstate how warm the body's inside really is. In contrast, rectal measurements sit closest to core temperature and are less affected by external factors, while tympanic can approximate core temp when done correctly but can be skewed by ear conditions or technique, and oral readings can be altered by recent foods, drinks, or mouth breathing. So the armpit site is generally the least accurate for core temperature.