Comparison of tympanic thermometry accuracy with rectal and axillar methods in children

Rectal route is a gold standard method of measuring fever, but it is invasive and stressful for parents and children. A recently used method is tympanic that has the advantages of safety, speed and compatibility but its accuracy is under question. In order to assess the accuracy of tympanic thermometry, 220 children within 3 months to 6 years old were selected and temperature was checked by rectal, axillary and tympanic methods. The mean rectal temperature, compared with tympanic and axillary, was higher (0.3oc and 0.1oc, respectively). There was a good correlation between right and left tympanic measurements (r=0.87, P<0.001), rectal and right tympanic (r=0.76, P<0.005), axillary and right tympanic (r=0.80, P<0.001), and axillary and rectal methods (r=0.74, P<0.001). The sensitivity, specificity and accuracy of tympanic method (with 38ocas cut off point) were 46.4%, 97.2 % and 90.9%. ROC curve analysis showed that the best cut off point for fever was 37 oc the sensitivity, specificity and accuracy were increased 92.9%, 90.1% and 90.4%, respectively, using this cut off point. Kappa coefficient showed a good correlation between rectal and tympanic methods. Tympanic thermometry, in comparison to axillary and rectal thermometry is an accurate, rapid, safe and comfortable method and the best cut off point for defining fever is 37oc.