As the basic sciences develop, temperature measurement methods and devices were improved. For hundreds of years both in clinics and home, mercury-in-glass thermometer was the standard of human temperature measurements. In this study, we aimed to compare tympanic infrared thermometers with the conventional temperature option, mercury-in-glass thermometer, which is historical standard in the clinical conditions.
Methods: A total of 102 randomly selected pediatric patients who admitted to our hospital were enrolled, and simultaneous temperature measurements were performed via axilla and external auditory canal with 3 different techniques. For external auditory recordings, infrared tympanic First Temp Genius for clinical use and Microlife IR 1DA1 for home usage were used. Classic mercury-in-glass thermometers were used for axillary recording. For each method, 886 measurements were performed.
Results: The mean results of the axillary mercury-in-glass thermometers, infrared tympanic First Temp Genius, and Microlife IR 1DA1 were 36.8 +/- 0.7, 37.5 +/- 0.9, 36.9 +/- 0.8, respectively. The Bland-Altman plot of differences suggests that 95% of the infrared tympanic clinical use thermometer readings were within the limits of agreement, which is +0.27 and -1.75 degrees C range of mercury-in-glass thermometer. The Bland-Altman plot of differences suggests that 95% of the tympanic home-use thermometer readings were within the limits of agreement, which is +0.98 and -1.27 degrees C range of mercury-in-glass thermometer. In our group, 15% of the patients were misdiagnosed as febrile with home-use tympanic thermometer, whereas this percentage was 4% with clinical tympanic thermometer. Also, 5% and 31% of febrile patients were misdiagnosed as afebrile with clinical tympanic and home-use tympanic thermometer, if axillary mercury-in-glass thermometer recording defines fever.
Discussion: Our results showed that there is a significant difference in each recording with different thermometers, and this variance was present in both higher and lower readings. We recommend thathome-use infrared tympanic thermometer could be used for screening but must not be considered as a tool to decide patients follow-up.