The FDA’s new draft guidance aims to address a longstanding issue in healthcare: the inaccuracy of pulse oximeters for people with darker skin tones. Pulse oximeters, devices that measure blood oxygen levels, became widely used during the Covid-19 pandemic but have faced criticism for providing less reliable readings for individuals with higher melanin levels in their skin.
These devices operate by sending light through the skin and measuring how much oxygen is in the blood based on the light’s absorption and reflection. However, darker skin can absorb more light, potentially leading to inaccurate oxygen measurements. Studies have shown that this issue disproportionately affects people of color, contributing to incorrect diagnoses and treatment delays. For instance, in one study published in 2022, blood oxygen levels in Black, Hispanic, and Asian patients were overestimated, leading to possible under-treatment, especially for Covid-19 patients.
Recognizing the gravity of the problem, the FDA has proposed updated guidelines for pulse oximeter manufacturers. One key recommendation is that clinical studies should include a diverse sample of at least 150 participants, with a minimum of 25% representing each skin tone group based on the Monk Skin Tone scale. This scale provides a more nuanced system for categorizing skin tones compared to simpler classifications.
The draft guidance also calls for manufacturers to clearly label devices with warnings about potential inaccuracies in pulse oximeter readings due to skin pigmentation. The FDA hopes that these steps will help ensure that devices are tested thoroughly and accurately, offering more equitable healthcare for all patients, regardless of skin color.
This draft guidance comes after years of research showing a significant performance gap between pulse oximeters used on individuals with light and dark skin. In particular, a 2022 study found that Black patients were more likely to have their oxygen levels underreported by pulse oximeters compared to blood-drawn readings. These inaccuracies were especially concerning in critical care settings, where timely oxygen administration can be the difference between life and death.
The FDA’s efforts to fix the pulse oximeter issue follow previous attempts to improve device accuracy. A 2013 guideline recommended that clinical studies include individuals from a range of skin tones, yet compliance was limited. Public health experts hope the new, more detailed guidance will be better enforced, although concerns remain about how strictly manufacturers will follow the rules.
Additionally, there are fears that many over-the-counter pulse oximeters—often sold directly to consumers—might not be covered by the new guidelines. These devices are not always subject to the same rigorous testing and oversight as medical-grade pulse oximeters used in hospitals. If the FDA’s guidance is limited to medical devices only, it could mean that many less-accurate devices on the market continue to be used by consumers without adequate protection or information.
Despite these concerns, experts see the FDA’s draft guidance as a step in the right direction. By encouraging manufacturers to test their devices on a diverse range of participants and labeling their products with clear warnings, the FDA is aiming to level the playing field for all patients. Public health experts, including those involved in the Health Law and Policy Clinic at Harvard, view this as an important move toward ensuring that pulse oximeters can deliver accurate and equitable results for all patients, regardless of their skin tone.
While the FDA is still reviewing public feedback and will finalize the guidelines after considering this input, the proposal has already sparked positive reactions from healthcare professionals. If the guidance is fully implemented, it could lead to significant improvements in pulse oximeter accuracy, helping to ensure that patients of all backgrounds receive the most accurate and timely care possible.
As the FDA works toward finalizing these guidelines, one can only hope that this step will pave the way for better, more equitable healthcare technology, and that manufacturers will fully comply with the standards needed to safeguard the health of all patients.
