Comparison of axillary, inguinal and tympanic temperatures to rectal temperatures in infants

The purpose of this study was to examine relationships of axillary, inguinal, and tympanic temperatures to rectal temperatures in infants from 24-42 weeks gestation. A total of 62 infants were included in this study, with infants studied both as a total group and by assignment according to gestational age: 24-27 weeks, 28-31 weeks, 32-35 weeks and 36-42 weeks. Analysis of variance was performed to determine if the axillary, inguinal, and tympanic measures differed significantly from the rectal measures depending on gestational age groups. Least significant difference revealed infants 24-27 weeks gestation had axillary-rectal temperature and inguinal-rectal temperature differences that were significantly different than other age groups. There was also a significant difference in rectal-tympanic temperatures, between infants with gestational ages 36-42 weeks and infants 24-31 weeks. Pearson r was performed to determine the strength of correlation between the rectal and other routes. Overall, the axillary method had the strongest correlation with the rectal method, followed by the inguinal method. The correlation of the axillary, inguinal, and tympanic temperatures with the rectal temperature increased as gestational age increased. Correlation of the axillary, inguinal, and tympanic temperatures to the rectal temperature was extremely poor in infants 24-31 weeks gestation regardless of route. Moderate correlations were noted in infants 32-42 weeks gestation in the axillary and inguinal routes, but not between the tympanic route and other routes.