A systematic review of major COPD clinical trials indicates that race-based correction in pulmonary function testing (PFT) may contribute to the exclusion of minority groups from these studies. The review, encompassing 21 randomized controlled trials (RCTs) with over 70,000 participants, highlights that while race-based correction is frequently used, it is often inconsistently reported. This practice may lead to the underrepresentation of racial minorities, particularly Black individuals, in COPD research.
The Impact of Race-Based Correction
Race-based correction involves adjusting predicted lung function values based on a patient's race. Historically, these adjustments have resulted in lower predicted values for Black and Asian individuals compared to White individuals. In COPD diagnosis and management, this means that racial minorities require lower absolute lung function values for their lung disease to be considered equally severe, potentially leading to underdiagnosis and undertreatment.
According to the study, race-specific equations can cause predicted values of lung function, such as FEV1 and forced vital capacity (FVC), to vary by 4–6% for Asian individuals and 10–15% for Black individuals compared to White individuals. The use of these equations has been increasingly questioned for representing implicit bias and potentially resulting in the underdiagnosis of lung disease in racial groups.
Underrepresentation in Clinical Trials
The review found that Black participants represented less than 5% of study participants in the included trials, with other racial minorities also being underrepresented. Given that FEV1 cutoffs are commonly used as inclusion criteria in COPD trials, race-based correction may inadvertently exclude minority groups by requiring them to have lower absolute FEV1 values to qualify.
Methodological Details
The systematic review analyzed RCTs evaluating inhaler therapy in COPD patients, focusing on trials with a sample size of 1500 or more. Data extraction included study design, population demographics, pulmonary function testing values, and the usage of race-based correction. Corresponding authors were contacted for additional information when details were lacking in publications.
Findings and Analysis
Of the 21 included studies, only four explicitly mentioned the use of race-based correction. However, after contacting authors and examining citations, it was confirmed that the majority of articles employed race-based correction. The studies cited references that apply correction factors to Asian and Black populations, assuming lower lung function in these groups.
Expert Commentary and Implications
The authors emphasize the need for standardized reporting guidelines to increase transparency regarding the use of race-based correction in clinical trials. They also call for improved data collection on race in clinical trials, including parameters of race in excluded participants for future analyses.
In 2023, the American Thoracic Society (ATS) released a statement recommending the use of race-neutral equations in pulmonary function testing. This review establishes a baseline for the usage of race-based correction in current research and highlights the need to develop standard reporting guidelines to increase transparency surrounding its usage in clinical trials. Further research is required to examine the effect of race-neutral equations on the inclusion of racial minorities in clinical trials and their impact on clinical outcomes in patients with COPD.
