
The study authors highlight prior research that has found pulse oximeter devices often give artificially high blood oxygen levels for people with darker skin because the melanin in their skin absorbs light differently than lighter skin. Furthermore, these medical devices are often calibrated using mostly light-skinned people — a systemic bias in product development that has caused significant disparities in follow-up care.
To document these racial disparities in care, the researchers examined data from 3.5 million visits to more than 100 Veterans Health Administration emergency departments between 2014 and 2018. Their analysis revealed that Black patients with the same pulse oximetry readings as White patients receive significantly less follow-up care.
The authors call out that prior research revealed disparities among inpatients who received follow-up arterial blood gas tests; Black patients had lower actual blood oxygen levels than White patients with identical pulse oximeter readings. Thus, the authors’ latest finding suggests that Black patients are likely missing out on crucial care, such as receiving supplemental oxygen.
“Our findings highlight how systemic bias in product development and commercialization can have downstream consequences for clinical care and underscore the importance of representation in all steps of the scientific process,” said first author Marcella Alsan, the Annie and Ned Lamont Professor of International Studies and a professor of health policy and economics at Stanford University.

