What causes inaccurate body temperature readings?

Inaccurate body temperature readings can result from several factors, including the method of measurement (oral, rectal, axillary, or tympanic), which can yield different results. Environmental influences, such as extreme temperatures or recent physical activity, can also affect readings. Additionally, improper use of thermometers, such as not placing them correctly or not allowing them to equilibrate, can lead to errors. Finally, certain medical conditions or medications may alter the body's temperature regulation, causing false readings.