According to scientific papers Apple watches are the most accurate PPG watches – can we use those to do physiolological research with those?

Apple watches are the PPG watches which are studied best in these scientific papers: Apple watches are scientifically validated for the activities they are studied with in these papers, and that is for instance treadmill runs up to about 15 km/h compared to a 3 channel gold standard ECG device, but Apple watches where also …