Years of research have showed that pulse oximeters yield less accurate readings for people with darker skin tones, and now the US Food and Drug Administration is proposing guidance to help make these devices more reliable and less biased.

The U.S. health regulator on Monday proposed a new guidance for widely used blood oxygen monitoring devices to improve their performance across skin tones amid growing evidence that the current ones are not reliable for patients with darker skin.

Rather than relying on those testing the devices to judge skin tones, the draft guidance suggests manufacturers should use both the newly developed Monk Skin Tone scale and another scale, called the individual typology angle (ITA), which is based on spectrophotometric measurements.

The agency is proposing that device manufacturers improve their testing to including larger, more diverse sample sizes.

A Food and Drug Administration (FDA) draft guidance would require manufacturers of pulse oximeters to gather far more clinical data to show the devices accurately work across a range of skin

The FDA's draft recommendations for pulse oximeters aims to include clinical studies involving at least 150 participants with diverse skin tones.

The Food and Drug Administration on Monday bolstered its recommendations for pulse oximeter testing following public uproar over how inaccurate readings led to different medical care for patients of color during the pandemic.