Measuring the body temperature: how accurate is the Tempa Dot?
Van den Bruel A., Aertgeerts B., De Boeck C., Buntinx F.
INTRODUCTION: We evaluated the accuracy of a disposable, sterile thermometer that is practical in use and holds no risk of cross-infections. METHODS: a cross-sectional study was set up in which we compared the Tempa Dot with the mercury thermometer in adults and children. Subjects were recruited from general practice and a paediatric ward. The mercury thermometer was used orally in subjects over 2 years of age and rectally in children up to 2 years old. The Tempa Dot was used either orally or axillary. RESULTS: The total population consisted of 212 patients, of which 131 children were younger than 16 years old. Their mean age was 17.3 years old, ranging from 1 month to 76 years. The mean difference between the mercury thermometer and the Tempa Dot, used orally or axillary, was 0.04 degrees C. For children between 0 and 16 years old, the mean difference was 0.08 degrees C. Agreement between the two methods as assessed with regression analysis and Bland and Altman plots was very good. ROC curve analysis suggests cut-off points of 37.2 and 37.6 degrees C to detect fever for the Tempa Dot at the oral and the axillary site respectively. Sensitivity and specificity were 100.0% and 79.0% for the total population, measuring orally and 100.0% and 95.9% axillary. In children, sensitivity and specificity were 100.0% and 83.1% orally, and 100.0% and 95.4% axillary. Using a single cut-off point for both measuring sites, namely 37.5 degrees C, sensitivity dropped and specificity increased for the oral site. For the axillary site, sensitivity remained unchanged and specificity was somewhat less. CONCLUSION: the Tempa Dot is a reliable alternative for the mercury thermometer. In clinical use, a cut-off point of 37.5 degrees C for both the oral and axillary site is most appropriate.