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As we continue our series highlighting bias in clinical formulas, we are featuring a diagnostic tool widely used to assess lung function. Spirometry helps physicians diagnose and manage various respiratory diseases, including asthma and chronic obstructive pulmonary disease, or COPD. Spirometry relies on many factors including race, age, gender, and height, often producing varied results within individuals. What isn’t as widely known is that the calculations used to determine how well someone’s lungs function include questionable adjustments for race or ethnicity.

Impact on Patients and Providers
Spirometry was designed to use a scaling factor for those not identified as “White.” Test operators are responsible for inputting the race or ethnicity, but how they determine a patient’s particular race or ethnicity can differ drastically. Some practitioners rely on self-identification, while others use their own visual judgment and assumptions. Current recommendations include using race for individuals identified as White (i.e., European ancestry), African American, Northeast Asian, Southeast Asian, and other/mixed. The use of race has been called into question, as race is a social construct and its use in lung function testing began in the 18th and 19th centuries resulting in the unequal treatment of non-Whites. Unfortunately, many operators are unaware of the implications of the built-in race correction factor and its history.

Spirometer results are critical in diagnosing and treating chronic lung diseases. The use of race in spirometry has been shown to underestimate the risk of poor outcomes for non-Whites. Research has found that Asian Americans and Black Americans of all ages are assessed lower lung function than White Americans when tested with a race/ethnicity adjusted spirometer. The built-in bias can have a dramatic impact on long-term patient outcomes. Appropriately diagnosing lung conditions and offering early intervention helps properly manage chronic lung conditions and slows the progression of the disease. Additionally, spirometry is used as part of various types of organ transplant eligibility including one’s own stem cells. When considering risk and eligibility for organ transplant, inaccuracy in test results can have life-threatening consequences. Race correction can cause otherwise identical patients to be treated differently based solely on ethnicity and race.

What Should be Done
To ensure accurate diagnosis and treatment decisions based on spirometry testing, it is essential for healthcare providers to be aware of “race correction” technology. They should also be educated on where to check equipment guidelines and how to turn off standardization, if necessary. Patient-centered care that is focused on the individual and their unique needs and provider education is critical for informed decision-making in this area. Being aware of the history and use of race in pulmonary care is an essential step to obtaining accurate information about each patient’s condition—regardless of race or ethnicity.

To ensure all practitioners are adequately educated in all facets of health equity, including biased clinical calculations, the Truity health equity platform provides physicians with real-time education and recommendations at the point of care. To learn more, visit