News Release

Assessing Race-Neutral Tests for Lung Function


A new study in the New England Journal of Medicine is the first to show the implications of adopting race-neutral equations when physicians are testing for lung function––though adjustment for race is already discouraged in these tests. Race adjustment is a longstanding, routine, but controversial practice in medicine that assumes that black patients have lower lung capacity than white patients. 

    Diao is a medical student at Harvard and MIT and a coauthor of the study. 

Diao told the Institute for Public Accuracy: “Race adjustment has profound effects on the many clinical and non-clinical decisions that are based wholly or in part on lung function testing. These are all derived from adjustments that assume healthy Asian and black patients naturally have lower lung function while healthy Hispanic and white patients naturally have higher lung function. Therefore, removing race led to the opposite effect, making Asian and black patients appear more sick than before and Hispanic and white patients appear less sick than before.

“Our study quantified the effects of these changes on defining and staging lung disease, determining eligibility for certain jobs, and determining payments amounts for disability compensation.” Other outcomes are also possible but the authors were unable to quantify them, such as insurance coverage for treatments, eligibility for clinical trials, monthly insurance premiums, referral for lung transplant, and indication for ventilatory support in some disorders.

“While we can’t say how many people have been materially affected with the data we have, we tried to estimate the next best thing, which is how many people could have been affected. For some outcomes, like COPD [chronic obstructive pulmonary disease] severity, we expect the number to be quite close. For others, like disqualification from firefighting, the number will be substantially lower. Nonetheless, it’s clear that there is a tremendous amount at stake with race-based lung-function equations.

“Anecdotally, we have heard of numerous cases from physician colleagues about people who face challenges with obtaining employment their families depend on or proving to insurance that they are sick enough to qualify for treatments. Our study shows that these are not isolated cases, and that using or removing race can change clinical, occupational, and financial decisions for millions of Americans and reallocate billions of dollars in disability compensation.”

The article notes that among the 249 million people in the U.S. between the ages of 6 and 79 who can give high-quality lung function results, the use of race-neutral equations may reclassify lung function impairments for 12.5 million people, medical impairment ratings for 8.16 million, occupational eligibility for 2.28 million, grading of COPD for 2.05 million, and military disability compensations for 413,000. Moreover, annual disability payments would increase by more than $1 billion among black veterans, and decrease by $0.5 billion among white ones.

But not all spirometers, the tools that measure lung ventilation, have been changed to reflect race-neutral values. “Part of the challenge,” Diao said, “is inertia. When medical practice has been built around certain practices, it can be hard to undo collective habits. Another part involves beliefs of racial essentialism––that differences in lung function reflect natural and innate differences between biologically separate races. With this assumption, using race to define ‘normal’ for each group may seem like an appropriate way to make the equations more accurate. 

“As we’ve learned more about the unequal distribution of socio-environmental factors that cause lung damage, as well as the many drawbacks of using race, the tides have turned. Today, we recognize that defining different ‘normal’ values for different racial groups likely obscures underlying disease in racial minorities, normalizes socioeconomic and environmental exposures, and presents challenges when the patient’s race does not fit one of the specified categories, or when doctors incorrectly assume the patient’s race.”