ZURICH – Researchers from the European Society of Cardiology have found a huge variability between commercially available heart rate apps.
Their research was published recently in the European Journal of Preventive Cardiology.
“The problem is that there is no law requiring validation of these apps and therefore no way for consumers to know if the results are accurate,” said Dr. Christopher Wyss, an author of the research paper.
The study included 108 participants and tested the accuracy of four randomly-selected, commercially available heart rate apps using two smartphones. Some apps use contact photoplethysmography (touching the fingertip to the phone’s built-in camera) and others use non-contact photoplethysmography (camera is held in front of face).
Accuracy was assessed by comparing the results to the clinical gold standard measurements—the electrocardiogram and fingertip pulse oximetry.
In some apps there were differences of more than 20 beats per minute, compared to ECG in more than 20% of the measurements, the researchers found. The non-contact apps worked less well than contact apps, particularly at higher heart rates and lower body temperatures. The non-contact apps had a tendency to overestimate higher heart rates.
“Consumers and interpreting physicians need to be aware that the differences between apps are huge and there are no criteria to assess them,” said Wyss.