WVU Research Shows Smartwatch And Clinical Testing Measures Differ
13th October 2024
Wearables operate with photoplethysmography, or PPG, a technology that shines a light into the skin and produces a reflection of the blood moving just below the finger or wrist to record heart rate. In a hospital, an electrocardiography — ECG or EKG — machine measures the heart’s electrical activity through electrodes placed on the body.
“You’re looking at two things, one is blood flow and the other is the electrical signal of the heart,” Tenan said.
Clinicians and medical scientists are interested in heart rate variability because it’s a biomarker for a patient’s general system health. Tenan said even if people don’t pay particular attention to the measure on their wearable, it still plays a part in their overall wellness picture indicated on the device.
“A lot of these devices will give something called a readiness score or a sleep score and one of the primary components of these is the heart rate variability measure,” he explained. “People look at these scores to see how they’re doing overall, whether their fitness has improved, that sort of thing. But, if a composite is full of a measure that’s biased, how accurate is it going to be?”