Though convenient, oral, tympanic membrane, axillary, and temporal artery thermometers (AKA “peripheral thermometers”) may not be highly accurate in measuring body temperature.
A 2015 systematic review and meta-analysis of the performance of peripheral thermometers involving 75 studies (mostly in adults) found that compared to central thermometers (eg, pulmonary artery, urinary bladder, rectal), peripheral thermometers had a low sensitivity (64%, 95% CI 55%-72%), but much better specificity (96%, 95% CI 93%-97%) for fever (most commonly defined as 37.8° C [100° F] or greater).1
In the same study, for oral electronic thermometers, sensitivity was 74% with a specificity of 86%. For temporal artery thermometers, sensitivities ranged from 26% to 91%, while specificities ranged from 67% to 100%. For tympanic membrane thermometers, sensitivities ranged from 23% to 87%, with a specificity of 57% to 99%.
A 2016 study involving adult emergency department patients reported the sensitivity of peripheral thermometers (vs rectal temperature 38 C [100.4] or higher) as follows: oral (37%), tympanic membrane (68%), and temporal artery (71%). Specificity for fever was >90% for all peripheral thermometers. 2
So, it looks like while we may be pretty comfortable with a diagnosis of “fever” when our patient with chills has a high temperature recorded by a peripheral thermometer, lack of fever alone by these devices should not veer us away from the possibility of systemic infection. When in doubt and if possible, check a rectal temperature.
- Niven DJ, Gaudet JE, Laupland KB. Accuracy of peripheral thermometers for estimating temperature: A systematic and meta-analysis. Ann Intern Med 2015;163:768-777. https://www.ncbi.nlm.nih.gov/pubmed/26571241
- Bijur PE, Shah PD, Esses D. Temperature measurement in the adult emergency department: oral tympanic membrane and temporal artery temperatures versus rectal temperature. Emerg Med J 2016;33:843-7. https://www.ncbi.nlm.nih.gov/pubmed/27334759
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