Many medical devices, like thermometers, pulse oximeters, and heart rate monitors, use light to measure important health indicators non-invasively. However, research has shown that these devices may not work as well on people with darker skin, potentially leading to health disparities. One reason is that these devices were often tested primarily on people with lighter skin, and current testing standards do not adequately account for different skin tones. For example, pulse oximeters are only required to test a small number of people with darker skin, but there are no clear guidelines on how to define or measure "dark skin."

This study aims to address this issue by better understanding how devices perform across a wide range of skin colors, particularly in diverse populations like those in India. The study will use both subjective methods (like skin tone scales) and objective methods (like colorimeters, which measure skin color more precisely) to categorize skin tones. It will also explore whether low-cost color measurement devices can be as accurate as expensive ones, which could improve access to accurate healthcare in resource-limited settings.

The goal is to provide more accurate data on skin tone diversity to help improve the design, testing, and regulation of medical devices, ensuring that everyone, regardless of skin color, receives the same level of care.