Racial Disparities in Pulse Oximetry Cannot Be Fixed With Race-Based Correction

Pulse oximeters play a critical role in health monitoring. Pulse oximeter (SpO2) measurements exhibit statistical bias as a function of race, causing higher rates of occult hypoxemia (missed detection of dangerously low oxygenation) in patients of color. This paper further characterizes the statistical distribution of pulse oximeter measurements and shows higher variance for patients racialized as Black compared to those racialized as white. Analyzing hypoxemia detection as a statistical detector, the authors show that no single race-based correction factor or race-dependent threshold can equalize detection performance between Black and white patients. To achieve racially equitable pulse oximetry, improvements must be made to the device and measurement process itself, not just to hypoxemia thresholds.