A comparison of four infrared tympanic thermometers with tympanic membrane temperatures measured by thermocouples

Purpose: To compare measurements made with four infrared tympanic thermometers (Genius(R), Thermopit(R), Quickthermo(R), and Thermoscan(R)) with those recorded from thermo couples positioned in the contralateral ear. Methods: Four tympanic thermometers were evaluated in 50 healthy volunteers (12 female and 38 male). Temperatures were measured, in random order, at the right tympanic membrane four times and the highest temperature was considered to be the true value measured by each thermometer. The control temperature was measured at the left tympanic membrane using Mon-a-Therm(R) thermocouples. Results: The tympanic membrane temperature measured by Genius(R) correlated best with the Mon-a-therm(R) measurement (TM) (r = 0.74). The tympanic membrane temperatures measured by Thermopit(R), Quickthemo(R), and Thermoscan(R) correlated moderately with TM (r = 0.56, 0.63, and 0.58, respectively). Mean differences between TM and each temperature (TG, TTP, TQ, and Trs) were -0.3, 0.73, 0.42, and -0.3 degrees C, respectively. Likewise standard deviations were 0.33, 0.37, 0.35, and 0.35. Conclusion: We conclude that all but the Thermopit(R) (TTP) are similarly useful for the management of patients during anaesthesia.