Masimo SET® Pulse Oximetry Performed Accurately on Hospitalized Newborns of All Skin Tones in Largest-Ever Prospective Real-World Study

NICU Study Adds to the Evidence Demonstrating SET^®'s Accuracy in Challenging Real-World Settings, With No Clinically Significant Differences in Performance Across Skin Pigmentation Categories or Race and Zero Occult Hypoxemia in Black or Hispanic Newborns

Masimo (NASDAQ:MASI) today announced the findings of a study evaluating the accuracy of Masimo SET^® pulse oximetry among critically ill neonates and demonstrating less than 1% overall statistical bias. Importantly, there were no clinically meaningful skin pigmentation-related discrepancies and no occult hypoxemic events among Black or Hispanic patients, and in only one Caucasian patient overall. The Neonatal Pulse Oximetry Accuracy and Disparities by Skin Pigmentation (NeoPODS) study findings were presented from the podium at the Pediatric Academic Society in Boston, MA on Monday, April 27^th at 10 am EST by lead author Dr. Heather Siefkes on behalf of colleagues at the University of California, Davis and the University of Mississippi, Jackson, alongside online publication in the Journal of Pediatrics. As the authors noted, "[W]e found no evidence of clinically meaningful skin tone-related discrepancies, suggesting equitable monitoring performance for this device in this clinical setting."¹

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Masimo RD SET® Neo Pulse Oximetry Sensor

These promising results—from an NIH-funded study that exclusively evaluated Masimo SET^® in a vulnerable, clinically fragile patient population—add to previously published evidence of its strong performance under the most challenging real-world conditions across all skin tones. The INSPIRE feasibility study, published late last year, showed that SET^® pulse oximetry performed accurately on critically ill adult medical ICU patients of all skin tones, without any occult hypoxemic events²—results similar to the newly published NICU findings,¹ as well as prior evaluations of Masimo SET^®'s accuracy by skin tone.^3-6 The results of the full INSPIRE study—involving approximately 500 adult patients—are expected to be published later this year.

As Dr. Siefkes' team points out, even when conducted prospectively, with real-world patients, past studies of pulse oximetry accuracy by skin tone in newborns have not used quantitative, objective measurements to classify pigmentation, or have other methodological shortcomings and limitations. Some prior studies have found that oxygen saturation measured by noninvasive pulse oximetry (SpO₂) can overestimate arterial blood oxygen saturation (SaO₂), which can lead to occult hypoxemia. Noting that accurate detection of hypoxemia is especially important in NICU patients, since it drives many care pathway decisions, the NeoPODS researchers thus set out to conduct a prospective accuracy study in this patient population, hospitalized NICU patients, with rigorous technical methodology: tightly paired, time-synchronized SpO₂-SaO₂ measurements and objectively classified skin pigmentation across a range of gestational ages using the same sensors and monitors for all patients. Their primary outcome was the mean bias between paired, simultaneously measured SpO₂ and SaO₂ values, and their secondary outcome, understanding how that bias differed by skin tone.

The researchers enrolled patients between July 2022 and July 2025 at two tertiary NICUs at UC Davis and UM Jackson. The patients were hospitalized newborns up to ten days old, of at least 26 weeks gestational age, with an indwelling arterial catheter and at least one clinically indicated arterial blood draw. Masimo RD SET^® Neo sensors connected to Radical-7^® Pulse CO-Oximeters^® and Root^® monitoring platforms were used to continuously record SpO₂ data before, during, and after arterial blood gas (ABG) sampling. SaO₂ values were directly measured with on-site laboratory analyzers and then paired with the corresponding average SpO₂ for the 30 seconds preceding each blood draw. In addition to recording parent-reported race, each patient's skin tone classification was objectively assessed with a variety of methods, including melanin index and individual typology angle (ITA)—the latter a continuous, quantitative measure of skin pigmentation recommended by the FDA in their 2025 draft guidance for pulse oximeter manufacturers.⁷ Data was captured by a SkinColorCatch device, and visual scoring was performed by clinicians blinded to each other's observations using the Massey-Martin and the Fitzpatrick scales.

From among 100 newborns enrolled over the three years, 136 paired SpO₂-SaO₂ readings collected from 70 patients met the technical criteria for inclusion in the final analysis. The patients' median gestational age was 28.4 weeks and median gestational weight was 1085 grams (very low birth weight). As identified by their parents, 40% of the patients were Black and 23% were Hispanic. As objectively assessed, their skin pigmentations spanned the full range of ITA classifications and most, but not the darkest, points of the Massey-Martin and Fitzpatrick scales.

The researchers found that overall mean bias between noninvasive SpO₂ and invasive SaO₂ was -0.98% 2.80% (95% confidence interval, -1.45% to -0.52%), which is not a clinically significant amount, and means that, on average, SpO₂ slightly underestimated, not overestimated, SaO₂. In fact, there was only one data pair meeting the definition of occult hypoxemia (SaO₂<88% when SpO₂≥92%), collected from a patient with the lightest ITA skin tone classification; there were zero cases of occult hypoxemia among Black or Hispanic patients.

Turning to accuracy by skin pigmentation, the researchers found that across the objective classification measurements, as well as parent-reported race, there were no statistically or clinically significant differences in mean SpO₂-SaO₂ bias. For melanin index and ITA classification, when analyzed continuously, bias became slightly less negative with lighter skin pigmentation, but with statistical significance only when ITA analysis was restricted to each patient's first measurement. There was no significant difference in bias comparing the 3 darkest to the 3 lightest ITA classifications, with all categories except the lightest showing a small negative bias and no statistically significant trend in bias with increasing darkness or lightness. Analyzing bias by Fitzpatrick and Massey-Martin classifications, the researchers similarly found no statistically significant differences (including when analysis was restricted to the first data pair per patient).

The authors concluded that their study is "a novel prospective study of newborns using objective skin pigmentation and closely paired SpO₂ and SaO₂ measurements assessing pulse oximeter accuracy across skin tones. Our study did not find clinically meaningful pigmentation-related bias. We believe this study provides some reassurance on equitable and accurate care in the NICU for this specific device and population. Our study supports the need for additional age-specific and device-specific pulse oximeter performance assessments."

Heather Siefkes, M.D., Principal Investigator of the NeoPODS study and Associate Professor at the University of California Davis Children's Hospital, commented, "In this prospective study of critically ill newborns with tightly paired measurements, we found that pulse oximetry only slightly underestimated arterial oxygen saturation overall and did not demonstrate clinically meaningful differences across skin pigmentation. Bias varied with oxygen saturation, with a tendency toward overestimation at lower SaO₂ levels; however, this pattern was not modified by skin pigmentation. Our findings highlight the importance of continued age-, disease-, and device-specific evaluation of pulse oximeter performance."

Daniel Cantillon, M.D., Chief Medical Officer at Masimo, added, "Concerns about occult hypoxemia in vulnerable neonates, especially with darker skin tones, prompted this large, investigator-initiated and NIH funded real-world study applying rigorous scientific methods. Once again, we're highly encouraged to see Masimo's RD SET technology demonstrate less than 1% overall bias without occult hypoxemic events among Black or Hispanic infants. This is consistent with the recently published INSPIRE feasibility study results among critically ill adults in the ICU under similarly challenging conditions. However, as the authors note, these findings cannot be extrapolated to other pulse oximeter manufacturers untested on critically ill patients under real-world conditions."

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References

1. Siefkes H, Holla I, Giusto E, Tancredi D, and Lakshminrusimha S. Neonatal Pulse Oximetry Accuracy and Disparities by Skin Pigmentation (NeoPODS): A Prospective Study. J Ped. 21 Apr 2026. doi: 10.1016/j.jpeds.2026.115114
2. Travers A, Terry C, Merrell W, Heincelman M, Warden A, Goodwin A. INSPIRE: Feasibility of a Study Examining the Effect of Skin Pigment on Pulse Oximetry. CHEST Crit Care. 10 Sept 2025. DOI: 10.1016/j.chstcc.2025.100209.
3. Sharma V, Barker S, Sorci R, Park L, Wilson W. Racial effects on Masimo pulse oximetry: impact of low perfusion index. J Clin Monit Comput. 19 Jan 2024. https://doi.org/10.1007/s10877-023-01113-2.
4. Barker SJ, Wilson WC. Racial effects on Masimo pulse oximetry: a laboratory study. J Clin Monit Comput. 2023 Apr;37(2):567-574. https://doi.org/10.1007/s10877-022-00927-w.
5. Foglia EE, Whyte RK, Chaudhary A, Mott A, Chen J, Propert KJ, Schmidt B. The Effect of Skin Pigmentation on the Accuracy of Pulse Oximetry in Infants with Hypoxemia. J Pediatr. 2017 Mar;182:375-377.e2. https://doi.org/10.1016/j.jpeds.2016.11.043.
6. Marlar AI, Knabe BK, Taghikhan Y, Applegate RL, Fleming NW. Performance of pulse oximeters as a function of race compared to skin pigmentation: a single center retrospective study. J Clin Monit Comput. 2025 Feb;39(1):119-125. https://doi.org/10.1007/s10877-024-01211-9.
7. Pulse Oximeters for Medical Purposes – Non-Clinical and Clinical Performance Testing, Labeling, and Premarket Submission Recommendations. Draft Guidance for Industry and Food and Drug Administration Staff. January 7, 2025.

About Masimo

Masimo (NASDAQ:MASI) is a global medical technology company that develops and produces a wide array of industry-leading monitoring technologies, including innovative measurements, sensors, patient monitors, and automation and connectivity solutions. Our mission is for our innovations to empower clinicians to transform patient care. Masimo SET^® Measure-through Motion and Low Perfusion™ pulse oximetry, introduced in 1995, has been shown to outperform other pulse oximetry technologies in over 100 independent and objective studies, which can be found at www.masimo.com/evidence/featured-studies/feature. Masimo SET^® is estimated to be used on more than 200 million patients around the world each year and is the primary pulse oximetry at all 10 top U.S. hospitals as ranked in the 2026 Newsweek World's Best Hospitals listing. Additional information about Masimo and its products may be found at www.masimo.com.

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