Subjective assessment of fever by parents: comparison with measurement by noncontact tympanic thermometer and calibrated rectal glass mercury thermometer.

STUDY OBJECTIVE

To assess the ability of parents to subjectively evaluate their children for fever and to compare their assessments with temperature measurements made with the use of a noncontact tympanic (NCT) or rectal glass mercury thermometer. A secondary goal was to assess how well a recently developed definition of fever for NCT thermometers, when used in the ear-equivalent mode (temperature of 37.7 degrees C or more), performed in a clinical situation.

METHODS

This 6-month prospective observational study employed a convenience sample of 180 children, aged birth to 4 years, who presented to the emergency department of a tertiary care children's hospital. Parents were asked to subjectively assess whether their child had a fever. The child's temperature was then measured with an NCT thermometer (three times in the rectal-equivalent mode and three times in the actual-ear mode). Both the subjective assessment and the NCT temperatures were compared with the rectal temperature measured by a rectal glass mercury thermometer.

RESULTS

The mean age of participants was 14.6 +/- 11.8 months (range, 2 days to 48 months); 56% were boys. The sensitivity of parental detection of fever by subjective means was 81.8% and the specificity 76.5%. The parent and the rectal glass thermometer agreed 79% of the time (95% confidence interval [CI], 73% to 85%). The sensitivity of the first temperature reading obtained with the NCT thermometer in rectal-equivalent mode was 74.7%, and the specificity was 96.3%. The NCT thermometer and the rectal glass thermometer agreed 84% of the time (95% CI, 78% to 89%). Use of the proposed definition of fever for NCT thermometers, when used in the ear-equivalent mode, caused sensitivity of a single measurement for fever to drop to 53.5%.

CONCLUSION

Parental subjective assessment of fever agreed with the presence of fever as measured by rectal glass thermometer in 79% of cases. Specificity was improved with the use of the NCT thermometer. The recently proposed definition for fever for NCT thermometers, when they are used in the ear-equivalent mode, does not appear to be validated by the current data.