Dark Skin, Bad Data: Pulse Oximeters in Detroit

By Franklin Everett Shaw

March 10, 2026

The little plastic clip, perched on a fingertip, promised reassurance. A simple number, a percentage, displayed on a tiny screen: blood oxygen saturation. But for many Detroiters with darker skin, that number might be a lie.

Pulse oximeters, those ubiquitous devices that became lifelines during the COVID-19 pandemic, are demonstrably less accurate on individuals with darker skin pigmentation. This isn’t a theoretical concern; it’s a real-world disparity with potentially devastating consequences, especially in a city like Detroit, where a significant portion of the population identifies as Black or African American. This isn’t about blaming the device; it’s about understanding its limitations and advocating for better healthcare.

The problem stems from the way pulse oximeters work. They shine light through the finger and measure how much is absorbed by oxygenated and deoxygenated hemoglobin. Melanin, the pigment responsible for darker skin tones, also absorbs light, interfering with the oximeter’s readings. This interference can lead to falsely high readings, masking true hypoxemia (low blood oxygen) and delaying crucial medical intervention. Studies have shown that the error rate is significantly higher in individuals with darker skin, potentially leading to missed diagnoses and poorer outcomes.

So, what can Detroiters with darker skin do to navigate this flawed system? Here’s a step-by-step guide to using pulse oximeters more effectively and advocating for better healthcare:

Understand the Limitations: The first step is acknowledging that pulse oximeters are not perfect, especially for individuals with darker skin. Don’t rely solely on the oximeter reading to determine your health status.
Establish a Baseline: Before you’re sick, take several readings with your pulse oximeter when you’re feeling healthy. Note the readings and the conditions (e.g., room temperature, activity level). This will give you a baseline to compare against when you’re not feeling well.
Optimize Measurement Conditions: Ensure your hands are warm. Cold hands can constrict blood vessels and affect the reading. Remove any nail polish, especially dark colors, as it can interfere with the light transmission. Sit still and avoid moving your hand during the measurement.
Observe Other Symptoms: Don’t rely solely on the pulse oximeter reading. Pay attention to other symptoms of low blood oxygen, such as shortness of breath, chest pain, confusion, and bluish discoloration of the lips or face. These symptoms are crucial indicators, regardless of what the oximeter says.
Communicate with Your Doctor: Be upfront with your doctor about your concerns regarding pulse oximeter accuracy. Share your baseline readings and any discrepancies you observe. Ask them to consider your skin tone when interpreting the results.
Consider Arterial Blood Gas (ABG) Testing: If you have concerns about the accuracy of your pulse oximeter reading, especially if you’re experiencing symptoms of low blood oxygen, ask your doctor about an arterial blood gas (ABG) test. This test measures the oxygen and carbon dioxide levels in your blood directly and is considered the gold standard for assessing blood oxygenation. It’s more invasive, but far more accurate.
Advocate for Change: This is where Detroiters can truly make a difference. Contact your local representatives and advocate for research into and development of more accurate pulse oximeters for all skin tones. Support organizations working to address healthcare disparities in Detroit.

Specific challenges in Detroit exacerbate this issue. The city’s history of systemic racism and healthcare disparities means that many residents already face barriers to accessing quality medical care. The inaccurate pulse oximeter readings can further compound these inequalities, leading to delayed diagnoses and poorer health outcomes.

Common mistakes developers make when designing medical devices, including pulse oximeters, often stem from a lack of diverse representation in the testing and development phases. Devices are often tested primarily on individuals with lighter skin tones, leading to biased algorithms and inaccurate readings for individuals with darker skin. To overcome this, developers need to prioritize diversity in their testing populations and use data-driven approaches to identify and mitigate biases in their algorithms.

Here are some local Detroit resources and organizations fighting for equitable healthcare:

Detroit Health Department: Provides information on health services and resources available in the city.
Wayne State University’s Center for Health Equity and Community Knowledge in Urban Settings (CHECK-US): Conducts research and promotes health equity in Detroit.
The Detroit Equity Action Lab (DEAL): Works to address systemic racism and promote racial equity in Detroit.
Black Mothers’ Breastfeeding Association: Addresses health disparities in maternal and infant health.

These organizations are working to address the root causes of healthcare disparities in Detroit and advocate for policies that promote health equity.

The fight for accurate medical devices is a fight for health equity. It’s about ensuring that everyone, regardless of their skin tone, has access to the tools and resources they need to stay healthy. By understanding the limitations of pulse oximeters, advocating for better technology, and supporting local organizations, Detroiters can play a crucial role in creating a more equitable healthcare system for all. Don’t let a faulty reading dictate your health; empower yourself with knowledge and demand better. The future of healthcare in Detroit depends on it.