The quantititve scientist Rob ter Horst has tested more than 100 smartwatches on YouTube:
https://www.linkedin.com/in/rob-ter-horst-90756a4a/?originalSubdomain=at
Peter H. Charton: Biomedical Engineer specialising in signal processing for wearables:
https://www.linkedin.com/in/peterhcharlton/?originalSubdomain=uk
Has written a paper about smartwatches:
«The 2023 wearable photoplethysmography roadmap»
https://iopscience.iop.org/article/10.1088/1361-6579/acead2
And Peter Gamma, Physiologist & Director of the Meditation Research Institute Switzerland (MRIS):
https://www.linkedin.com/in/peter-gamma-7920031ab/?originalSubdomain=ch
Has reviewed smartwatches once more on many pages on www.petergamma.org:
https://petergamma.org/category/optical-heart-rate-sensor
And he has major doubts about the results which are currently available about smart watch accuracy studies. He supposes that smartwatches are inaccurate and deliver irreproducable data. And he has major doubts about the scientific results which where published on YouTube by smartwatch accuracy tester and post-doctoral researcher Rob ter Horst who is specialized in biological data analysis.
We therefore invite other independent tester who preferentially has access to an ECG treadmill such as the Schiller CS 200:
To repeat the protocol of a paper which was written by the cardiologists of the Cleveland Clinic performed in their research center in Ohio.:
Cardiovascular Diagnosis and Therapy 2019 Aug;9(4):379-385.
Accuracy of commercially available heart rate monitors in athletes: a prospective study
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6732081
We invite independent testers to repeat the protocol used in the above paper with the Polar H10, the Apple Watch 9 and eventually other smartwatches on an ECG treadmill for runs up to about 15 km/h. we are convinced that ECG treadmills are more accurate than the Polar H10 chest strap and the Apple Watch 9 for runs on a treadmill up to about 15 km/h. But we do not know of any scientific tests which have shown this to this date.
And we invite also developers who build their own treadmill:
https://petergamma.org/category/treadmill-calibration
and their own ECG device:
https://petergamma.org/category/ecg-devices
to participate in these tests. As well as other heart rate monitor users to test their devices on a ECG treadmill, as for instance DFRobot to test their latest heart rate monitors with this method:
and share their results on YouTube.