However, not everyone agrees that wearable data belongs in the EHR—at least not yet. Consider Hawley Montgomery-Downs, PhD, an associate professor of psychology at West Virginia University and researcher who says she was initially optimistic about wearable devices and their ability to monitor sleep.
“When it came out, I was very excited about the potential that it offered,” she says. “If it worked well and gave us the information that we needed, then my opinion was that it was going to revolutionize sleep science.”
However, Montgomery-Downs says intentions for accuracy don’t necessarily translate into reality.
“As a scientist, I look at the marketing, smile, and nod,” she says. “Then I take the device into my laboratory and subject it to all of the rigors of evaluation compared to the gold standard, which is using electrodes and sensors to very precisely determine when someone is awake or asleep and what stage of sleep they’re in.”
Her research found that although some wearables were highly accurate at identifying when someone was asleep, they were just 50% accurate at identifying when that same individual was awake. “These devices tell you you’re sleeping better and more than you actually do,” she says. “And the worse you’re sleeping, the bigger the difference between reality and what the device is telling you.”
For example, they don’t record relatively brief awakenings, says Montgomery-Downs. This makes it difficult to correctly diagnose someone with sleep apnea who wakes up for 10-15 seconds every couple of minutes. Likewise, if someone with insomnia wakes up every 20 minutes but remains motionless, the device will assume that the individual is still asleep. Troublingly, this could give patients and physicians a false sense of wellness, she adds.
Studies show that the inaccuracies don’t just apply to sleep health data. For example, researchers at Stanford found that seven popular wearable fitness trackers had an error rate of more than 20% when it came to measuring calories burned.