Study Finds Masimo’s Pulse Oximeter to be Free From Racial Bias

Study Finds Masimo’s Pulse Oximeter to be Free From Racial Bias results from a study published this month have shown that Masimo’s flagship SET pulse oximeter provides accurate results regardless of the user’s race. There was no clinically significant difference found in the device’s accuracy when used on both Black and White patients.

Recently, many device manufacturers and healthcare providers, along with the Food and Drug Administration (FDA) have been focused on removing racial bias in pulse oximetry. The FDA held an advisory committee meeting earlier this month to discuss the issue and brainstorm potential solutions. But it looks like Masimo doesn’t need to worry about this issue on their end.

An analysis published a few months ago concluded that Hispanic, Asian, and Black patients seeking COVID-19 treatment in hospitals were likelier to have their low oxygen levels go unnoticed than their white counterparts. This could result in delaying the delivery of the required treatments like supplemental oxygen, which could have potentially fatal consequences.

The California-based company’s pulse oximeters, like most others of their kind, are worn on the fingertip to gauge blood oxygen saturation. The symptoms of hypoxemia, in which the body’s oxygen saturation drops dangerously low, include, but are not limited to, a rapid heart rate and labored breathing. Therein lies the importance of pulse oximeters, as they help patients keep regular tabs on their oxygen levels at different times.

In Masimo’s study, a total of over 7,000 pulse oximeter readings were analyzed from 39 Black and 36 White patients, which was conducted between October 2015 and July 2021. Steven Barker, M.D., Ph.D., the company’s chief science officer, and William Wilson, M.D., its chief medical officer, served as the leaders of the research.

When compared to arterial blood gas values obtained simultaneously, the SET device’s results deviated from the standard by an average of 1.42% for Black patients and 1.35% for White patients. By contrast, the FDA accepts a discrepancy of up to 3% between arterial blood gas readings and those from pulse oximeters.

The percentage of negative bias, which indicates an inclination to underestimate the actual measurement, was 0.2% for Black patients and 0.05% for White patients. Masimo says that the 0.15% difference has no clinical significance and that device users wouldn’t be able to see the biases because the SET pulse oximeters only measure to the nearest 1%.

“In conclusion, this retrospective study of healthy human volunteers monitored with Masimo RD SET pulse oximeter sensors showed an absence of clinically significant differences in accuracy between Black and White subjects,” said Barker and Wilson. In addition, they stated that the oximeters are tested on a similar number of people with light and dark skin to help ensure accuracy. 

Most pulse oximeters emit red and infrared light and then measure how much of that light is absorbed by the blood. However, Masimo’s oximeters go above and beyond this, according to Baker and Wilson. Masimo uses the regular algorithm in addition to four more signal-processing engines that work together to extract the true blood oxygen levels regardless of the subject’s skin pigment, movement, bone density, tissue thickness, and blood flow.

Also read, Study Finds Masimo’s Pulse Oximeter to be Free From Racial Bias