Masimo finds no difference in accuracy 

IRVINE, Calif. – Masimo has announced the findings of an abstract that reviewed retrospective pulse oximetry data and concluded there was no clinically significant bias based on ethnicity for black and white volunteer subjects monitored with the company’s SET pulse oximetry and RD SET sensors. 

A prior paper and letter to the editor purported to find “racial bias” in pulse oximetry measurements based on comparison data obtained from black and white patients from multiple sets of health record data using unspecified pulse oximeters and controls. 

Masimo Founder and CEO Joe Kiani responded to that paper, promising additional research to test the company’s technology. 

Dr. Steven Barker, chief science officer at Masimo, and Dr. William Wilson, chief medical officer at the company, reviewed data collected between October 2015 and July 2021, including 7,183 paired samples (3,201 black and 3,982 white) collected from 75 subjects (39 black and 36 white) who were screened with the same criteria to remove potential bias based on health conditions. 

The authors analyzed the data to determine the bias (the mean difference in paired SpO2 and SaO2 samples), precision (standard deviation of the difference) and accuracy (root mean squared error, ARMS) for both groups. They found a negative bias of 0.20% for black subjects, compared to a negative bias of 0.05% for white subjects, a difference of 0.15% – not clinically significant. They found precision of 1.40% for black subjects and 1.35% for white subjects. 

By comparison, the letter to the editor reported a difference of 8.1% in a cohort of black and white hospital patients – 54 times higher. 

Masimo is conducting additional studies.