Detecting fever in young infants: reliability of perceived, pacifier, and temporal artery temperatures in infants younger than 3 months of age.

OBJECTIVES Fever in young infants frequently triggers a laboratory evaluation because of the increased likelihood of serious bacterial infections. Reported fever by methods other than rectal thermometry is of concern. This study evaluates the validity of perceived, pacifier, and temporal artery (TA) temperatures. METHODS A convenience sample of 200 babies younger than 3 months of age presenting to an emergency department was evaluated for parental perception of fever and with TA, pacifier, and rectal temperatures. RESULTS The sensitivity and specificity of perceived and TA detection of fever were similar at 91 and 79, and 83 and 86, respectively. Febrile pacifier readings had a sensitivity of 99, but a specificity of only 46. CONCLUSIONS Rectal thermometry must remain the standard for infants younger than 3 months of age.