Racial Differences in Detection of Fever Using Temporal vs Oral Temperature Measurements in Hospitalized Patients

Temporal artery (forehead) thermometers are frequently used in hospitals, but studies of these thermometers lack details on racial composition of study populations.^1,2 Recent studies have found that pulse oximetry can lead to missed hypoxemia in Black patients.³ Similar racial differences in thermometry could lead to missed fever, delayed diagnoses, and increased mortality in Black patients. We evaluated the performance of temporal compared with oral thermometry in detecting fever in Black and White patients with infection.

This retrospective cross-sectional study involved adult patients admitted to 4 Emory hospitals between 2014 and 2021. The inclusion criterion was suspected infection, defined as a combination of body fluid cultures and antibiotics within 24 hours of hospital presentation.⁴ Patients self-reported their race and ethnicity during hospital registration. Patients who self-reported as Asian, Hispanic, or other were not included due to small sample sizes. For each patient, the first pair of oral and temporal temperatures measured within 1 hour of each other within the first day of hospitalization were included, with exclusion of measurements after receipt of acetaminophen (paracetamol). Oral temperatures were obtained with a Welch Allyn SureTemp Plus device (error rate, −0.016 °C with monitor mode as reference).⁵ Temporal temperatures were obtained with an Exergen TAT-5000 device (error rate, 0.11 °C with SureTemp as reference).² Paired oral and temporal measurements were compared using paired t tests in Black and White patients. In logistic regression stratified by race, association between route of measurement and fever (≥38 °C) was evaluated, controlling for demographics, hospital, and comorbidities. The analysis was repeated under varying fever cutoffs (37.8 °C, 38.3 °C, and 38.5 °C). A sensitivity analysis was performed on temperature measurements from the first hour of presentation. All analyses were performed using R version 3.6.1 (R Foundation). Statistical significance was set at P < .05 using 2-tailed tests. The Emory University institutional review board granted a waiver of consent.

There were 2031 Black patients and 2344 White patients with paired temporal and oral measurements (Table 1). Temporal temperature was lower than oral temperature in Black patients (36.98 °C vs 37.05 °C; difference, −0.07 °C; 95% CI, −0.10 to −0.04 °C; P < .001) but not in White patients (36.97 °C vs 36.95 °C; difference, 0.02 °C; 95% CI, −0.01 °C to 0.05 °C; P = .18), with no differences whether temporal or oral temperature was measured first. The prevalence of fever in Black patients was 10.1% with temporal and 13.2% with oral measurement. In White patients, prevalence was 10.8% with temporal and 10.2% with oral measurement. In logistic regression, temporal compared with oral measurement was associated with a significantly lower odds ratio (OR) of fever in Black patients (OR, 0.74; 95% CI, 0.61-0.90; P = .002) but not in White patients (OR, 1.07; 95% CI, 0.89-1.29; P = .47). This association was significant in Black patients at multiple fever cutoffs (Table 2). In 265 Black patients with paired measurements within the first hour of presentation, fever prevalence was 23.4% with temporal and 35.8% with oral measurement. In 281 White patients, prevalence was 27.8% with temporal and 26.0% with oral measurement. Temporal measurement had a lower OR of fever in Black patients (OR, 0.54; 95% CI, 0.37-0.79; P = .002) but not in White patients (OR, 0.91; 95% CI, 0.62-1.34; P = .62).

In this multicenter study, temporal compared with oral temperature measurement was associated with a lower odds of identifying fever in Black patients, while there was no significant difference in White patients. Health care systems routinely use fever cutoffs to trigger notification pathways such as sepsis alerts to systematize timely triage and antibiotic administration. Although the absolute difference between oral and temporal temperatures was small, the findings suggest that this discrepancy combined with commonly used fever cutoffs may lead to fever going undetected in many Black patients. The temporal artery thermometer used in this study has been evaluated in more than 100 clinical studies.¹ Research suggests skin emissivity may play a role in measurement variability, but the relationship between skin emissivity and pigmentation is uncertain.⁶ The racial difference found may stem from the medical device or from systemic mishandling of the device (eg, not scanning the forehead sufficiently). Differences in detection of fever could lead to delays in antibiotics and medical care for Black patients. Study limitations include (1) retrospective analysis, (2) inadequate power to evaluate differences in Asian and Hispanic patients, and (3) potential selection bias of patients with paired measurements.

Accepted for Publication: June 30, 2022.

Corresponding Author: Sivasubramanium V. Bhavani, MD, MS, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Emory University School of Medicine, 615 Michael St, Atlanta, GA 30322 (sbhava2@emory.edu).

Author Contributions: Dr Bhavani had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Bhavani, Wiley, Verhoef, Ofotokun.

Acquisition, analysis, or interpretation of data: Bhavani, Wiley, Coopersmith.

Drafting of the manuscript: Bhavani, Wiley.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Bhavani.

Obtained funding: Bhavani.

Administrative, technical, or material support: Bhavani, Wiley.

Supervision: Verhoef, Ofotokun.

Conflict of Interest Disclosures: Dr Coopersmith reported receipt of grants from the National Institutes of Health to his laboratory for work unrelated to this project. Dr Ofotokun reported receipt of grants from Merck. No other disclosures were reported.

Funding/Support: Dr Bhavani is supported by National Institutes of Health/National Institute of General Medical Sciences grant K23GM144867 and Dr Coopersmith is supported by grant GM072808 from the National Institute of General Medical Sciences and grant AA027396 from the National Institute on Alcohol Abuse and Alcoholism.

Role of the Funder/Sponsor: The supporting entities had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication.