A comparison of temperature measurements using three ear thermometers

Following anecdotal and research-based reports of inaccuracies encountered with the use of ear thermometers in patient care settings, this two-phase study was designed to compare the accuracy of three ear thermometers when used in a multioperator environment. The within-subject variation (limits of agreement) in ear temperature measurements obtained with the three ear thermometers in a multioperator condition by using an oral temperature reference standard ranged from +/- 1.25 degrees F to 1.85 degrees F. In multioperator, multisubject patient care environments using a pulmonary artery catheter core temperature as the reference standard, the limits of agreement for ear temperature measurements obtained with the three different ear thermometers ranged from +/- 2.19 degrees F to 2.85 degrees F. These results suggest that there is substantial variation in ear measurements and raise questions about the use of ear thermometers when there are multiple personnel taking temperatures, as occurs in hospital-based clinical practice environments. Handedness of the operator, position of the patient, and the ear used for measurement did not produce clinically significant variability in ear temperature measurements.