The Food and Drug Administration on Monday released much-anticipated testing recommendations for pulse oximeters. The draft guidance follows years of discussion about concerns that the devices can be less accurate for people with darker skin pigmentation than people with lighter pigmentation.
The agency outlined what information it would like to see in premarket submissions for medical pulse oximeters, including validation of the devices’ accuracy and ensuring the devices are tested across the range of skin pigmentations. The FDA also set out labeling recommendations, noting that devices should include a prominent statement if the device has been demonstrated to perform comparably across people with diverse skin pigmentations.
“Our draft recommendations are based on the best available science to help address concerns of disparate performance of pulse oximeters based on an individual’s skin pigmentation,” Michelle Tarver, director of the FDA’s Center for Devices and Radiological Health, said in a statement.
The FDA first warned about problems with pulse oximeter accuracy in 2021. CDRH had listed draft guidance on pulse oximeters among its priorities for the 2024 fiscal year but missed the cutoff.
While the guidance is focused on premarket submissions for new devices, the FDA also recommended that manufacturers of previously cleared pulse oximeters evaluate their devices for non-disparate performance and provide the data to the agency in new 510(k) submissions. The agency plans to also list online pulse oximeters labeled as having non-disparate performance.
The draft guidance does not apply to pulse oximeters for general wellness purposes, which include many of the devices sold in pharmacies or online.
The draft guidance will be open for comment for 60 days.
Testing specifics
Pulse oximetry is a non-invasive way of measuring blood oxygen saturation. Studies that have compared pulse oximeter results to arterial blood gas measurements have found that cases of hypoxemia, or low levels of oxygen in the blood, might be missed in people with darker skin because of accuracy problems with the devices.
The new guidelines increase the number of recommended clinical study participants to 150 people or more. It also outlines more specifics on how to measure representation in clinical trials.
The FDA recommended participants be distributed across three different groups based on skin tone, which can be assessed using the Monk Skin Tone scale and a separate, objective measurement. The Monk Skin Tone scale is a 10-shade scale intended to be more representative than the Fitzpatrick scale, which has been criticized by researchers for being inaccurate. The draft guidance specified that at least a quarter of participants should be distributed across each group.
By comparison, the last set of recommendations around pulse oximeters, which the FDA issued in a 2013 guidance, said that studies should include at least 10 people and include at least two people with “darkly pigmented” skin.
An article published in JAMA on Dec. 30 found that new draft guidance from the FDA could help address some of the equity problems with pulse oximeters.
After the FDA’s 2013 guidance was published, device summaries for pulse oximeters showed “low, but improving uptake of reporting participant diversity,” according to the paper.
However, there was “substantial variation” in reporting and “seeming confusion about concepts of skin tone, race and ethnicity, and national origin,” the study authors wrote. The lack of standardized information also made it difficult to compare accuracy across devices.
