Use of Race in Pulmonary Function Tests Isn’t Racist

Editor’s note: This blog post was initially submitted as a Comment to JAMA Network Open in response to the article, “Race-Specific and Race-Neutral Equations for Lung Function and Asthma Diagnosis in Black Children.” JAMA rejected our submission.

In their article “Race-Specific and Race-Neutral Equations for Lung Function and Asthma Diagnosis in Black Children,” Chang, et al. (2025) tacitly dismiss the possibility that variation in lung capacity by race could have a biological explanation. They’re mistaken. Harik-Khan, Muller and Wise (2004) observed that “socioeconomic, nutritional, and environmental variables” only explain 7–10% of the difference between black and white children vis-à-vis lung volume. Even when factoring in anthropometric factors the researchers could only explain half of the difference in lung volume. Stocks, Sonnappa and Lum (2014) also concluded that “African genes are associated with lower lung volumes.”

Furthermore, asthma is diagnosed based on clinical history and evidence of variability in expiratory airflow obstruction. Static measurement of forced expiratory volume exhaled in 1 second (FEV1), whether using a race-neutral or race-specific equation, is grossly inadequate to detect asthma, as shown by the poor sensitivity and specificity of the test for either black or white children. 

Taking the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) data presented in Chang, et al.’s article, the sensitivity and specificity using the race-specific equation for percent predicted FEV1 in black children were 18.2% and 81.3%, respectively. Using the race-neutral formula, sensitivity improved to 72.7%, but at the expense of specificity falling to 42.9%. In other words, the new, race-neutral equation missed fewer black children with asthma, but at the cost of misdiagnosing more black children with asthma who don’t actually have the disease. 

For white children in this dataset, the percent predicted FEV1 using the race-specific equation was similarly poor at 31.8%. Specificity was 85.1%. Using the race-neutral formula, sensitivity fell to 24.2%, while specificity remained relatively unchanged at 86.4%. Effectively, use of the race-neutral equation made a lousy result even worse for white children. The same pattern is seen in the Mechanisms of Progression from Atopic Dermatitis to Asthma (MPAACH) data, which the article also references.

The author’s conclusion of “structural racism” is unfortunately misplaced and divisive. As Witonsky, et al. (2022) noted, “spirometry could benefit from reference equations that incorporate genetic ancestry.” Moreover, predicted FEV1 is inadequate to detect asthma in both black and white children no matter the formula used. Rather than hunt for alleged “outdated racist practices” research should focus on truly improving the clinical diagnosis of asthma for all people.