Accuracy of Non-contact Infrared Thermometry Versus Rectal Thermometry in Young Children Evaluated in the Emergency Department for Fever

We evaluated the accuracy of a non-contact infrared thermometer compared with a rectal thermometer. Two hundred patients, ages 1 month to 4 years, were included in the study. Each child underwent contemporaneous standard rectal thermometry and mid forehead non-contact infrared thermometry. Clinical features, including chief complaint, recently administered antipyretic agents, and ambient temperature at the time of measurement, were included. Linear models were used to compare agreement between the 2 techniques, as well as to determine bias of infrared thermometry at different rectal temperatures. Multivariate linear models were used to evaluate the impact of clinical variables and ambient temperature. A linear relationship between rectal and infrared temperature measurements was observed; however, the coefficient of determination (r 2) value between was only 0.48 ( P < 0.01). Infrared thermometry tended to overestimate the temperature of afebrile children and underestimate the temperature of febrile patients ( P < .01). Ambient temperature and child age did not affect the accuracy of the device. In this study, non-contact infrared thermometry did not sufficiently agree with rectal thermometer to indicate its routine use.