Researchers at the University of Waterloo in Canada found that the Apple Watch can effectively predict stress levels.
The research team discovered that a reliable and precise stress prediction tool could be created using the Apple Watch ECG sensor data, according to My Healthy Apple.
The Sensor Data Can Increase The Apple Watch's Predictive Accuracy
Researchers discovered a strong correlation between individuals' reported stress levels at the time the readings were taken and their ECG data using the Apple Watch Series 6's ECG sensor.
This data included a person's heart acceleration and deceleration capacity, which can be used to determine their stress levels.
Then, using this data, machine learning algorithms were created to produce a prediction model, which were said to have a high level of precision, Mac Rumors writes.
Studies have demonstrated strong consensus in identifying the rhythm of the Apple Watch ECG compared to conventional 12-lead ECGs, claims Apple.
In a clinical investigation with 600 participants, the ECG sensor had 98.3% sensitivity for atrial fibrillation and 99.6% specificity for diagnosing sinus rhythm.
The study concludes that the Apple Watch has "promising" potential for stress prediction and suggests that even more data points might be included into stress models.
This will improve their predicted accuracy because the device captures additional health information, including sleep and activity data.
The results were rather encouraging given the nature of real-world measurements and the extremely brief duration of the ECG measurements carried out here in comparison to the norm, Mac Daily News.
The researchers also hypothesize that the Apple Watch might be used to support mental health treatment, providing exercises like deep breathing to counteract stress signals and detecting changes in mental health early.
Apple has not yet added a stress score option to its Health app, despite rival devices like Samsung, Fitbit, and Garmin offering one.
What Happens During The Research
For two weeks, participants in the study were provided with an iPhone 7 running iOS 15.0 and an Apple Watch Series 6 with an installed copy of the Apple Watch ECG software (WatchOS 8.3).
They were told to gather data six times a day, at intervals of roughly three hours, so that they can come up with relatively accurate information.
Participants were required to complete a stress questionnaire on the iPhone using the research team's app before their ECGs were taken.
The ECG data were then retrieved with the use of HealthKit, transformed into a CSV file, and then imported into Kubios to calculate HRV, as per My Healthy Apple's report.
Additionally, they examined additional factors like the effects of gender on stress prediction models and isolated the effects of age on those models.
Intriguingly, they also identified the influence of socioeconomic position on the stress prediction model as well as the influence of profession on a prediction model.
Apple hasn't yet made a stress monitoring tool available on its Watch platform, despite the fact that it could use the heart data and other activity data already available.
However, according to the tech giant, it might introduce a more powerful stress monitoring capability that makes use of extra sensors like EDA.
The other possibility is that the company plans to introduce this along with the upcoming AirPods, which supposedly have the ability to read EEG data and provide a more effective platform for monitoring mental health.