Researchers Concerned About Apple Watch False Positive Results

A group of researchers from the Mayo Clinic looked into the evaluation of patients who went to their doctors after receiving an alert from their Apple Watch informing them that they have abnormal pulse readings. And they found that many of these readings were false positives.

The research, titled “Clinical evaluation and diagnostic yield following evaluation of abnormal pulse detected using Apple Watch,” involved a retrospective review of four months' worth of medical records belonging to 264 patients who used an Apple Watch to monitor their pulse rates. The paper was published in the Journal of the American Medical Informatics Association (JAMIA).

Of the 264 patients, 41 said they received an alert from the Apple Watch explicitly telling them that they have abnormal pulse readings. The other 223 said they didn't receive an alert explicitly informing them of an abnormal pulse.

The researchers discovered that the Apple Watch was giving out a high number of false positives. Of the 264 patients included in the review, only 30 (11.4%) had a “clinically actionable cardiovascular diagnosis of interest.”

“The observation that new clinically actionable cardiovascular diagnoses of interest were diagnosed in only 11.4% of patients following medical evaluation as directed by the treating provider suggests a high false positive rate as a screening tool for undiagnosed cardiovascular disease,” the researchers wrote.

Interestingly, out of the 41 patients who received abnormal pulse alerts, only six had a clinically actionable cardiovascular diagnosis.

It's also worth noting that of the 264 patients, nearly half (48.9%) “had a preexisting cardiovascular diagnosis, and the most common department for initial evaluation was cardiology, in which the patient had a preexisting relationship,” the researchers said. The numbers indicated that the Apple Watch isn't a good “screening tool” for conditions related to heart ailments.

The researchers also noted that based on the patient data, real-world use of the Apple Watch's pulse rate sensor does not conform with the FDA's guidance, which states that the technology should not be used for people younger than 22 as well as for those previously diagnosed with atrial fibrillation.

The researchers are worried about what the high number of false positives could do to the healthcare sector, along with those who actually do not have any problems with their pulse rates.

“False positive screening results have the potential to lead to excessive healthcare resource utilization and anxiety among the 'worried well,'” the researchers continued.