Sehgal should know: he and his colleagues at the Center for Digital Health Innovation have compared the data reported by consumer wearable devices to relevant clinical gold standards in multiple studies over the past two years. They’ve found that very few devices currently on the market perform with the reliability one would expect from a medical-grade device.
And in fact wearable devices such as the Fitbit haven’t been clinically validated to perform at the same standards for reliability that the U.S. Food and Drug Administration uses for medical devices, such as the traditional blood-pressure cuff in a doctor’s office. Consumer wearables are marketed under the FDA’s less rigorous “wellness-focused” rubric.
Trister says that rather than tracking general activity, the most promising wearables target a specific thing. He cites startup Empatica’s Embrace wristband, which measures skin conductance—a signal that tends to rise as you get stressed—to detect an oncoming seizure (see “A Sleek Wristband That Can Track Seizures”). And Sehgal also points to devices being used in research labs that similarly measure the conductivity of the skin to help determine the severity of post-traumatic stress disorder among soldiers returning from war.
The end of this article suggests we’ll need time to see whether these devices can actually be used to help treat certain conditions. In the meantime, it would be interesting to know two things.
- What would it take to upgrade wearable devices for the masses: is it an issue of cost (all the testing an0d regulations would drive up the average price too much) or technology (these devices can’t yet be always reliable)?
- How would the average user know whether their particular device is unreliable? And if they could figure it out, do they have grounds for financial recourse?