The pacifier thermometer. Comparison of supralingual with rectal temperatures in infants and young children

To determine the correlation between supralingual temperatures obtained with a new electronic pacifier thermometer (Steridyne) and rectal temperatures obtained with a digital electronic thermometer.

Prospective study.

Pediatric emergency department and pediatric inpatient ward of a tertiary university hospital.

Convenience sample of 100 patients, aged 7 days to 24 months.

A supralingual and rectal temperature were obtained for each patient. For the first 30 patients, the time needed for the pacifier thermometer to signal a final, steady-state reading was recorded.

The mean +/- SD difference between rectal temperatures and supralingual temperatures adjusted upward by 0.5 degree F was -0.01 degree F +/- 0.42 degree F (statistically zero) (95% confidence interval, -0.09 degree F to 0.07 degree F). The correlation coefficient between supralingual and rectal temperatures was 0.95. Sensitivity and specificity of the pacifier thermometer for detecting fever (temperature > or = 100.4 degrees F [> or = 38.0 degrees C]) was 72.0% and 98.0%, respectively (positive predictive value, 97.3%; negative predictive value, 77.8%). Increasing supralingual temperatures by 0.5 degree F increased sensitivity to 92.0%, and decreased specificity to 76.0% (positive predictive value, 79.3%; negative predictive value, 90.5%). It took an average time of 3 minutes 23 seconds for the pacifier thermometer to display a steady-state temperature.

The pacifier thermometer evaluated here was found to be an accurate means of temperature measurement when recorded temperatures were adjusted upward by 0.5 degree F. The approximate 3 minutes required for a final temperature determination makes the pacifier thermometer most appropriate for use in low-volume ambulatory care settings and in the home. Further investigation of this device is recommended.