There's a Youtube channel from a Dutch researcher doing scientific tests on sleep and fitness tracking performance of wearables[1].
Ardently Apple devices and Oura are at the top in terms accuracy of what wearables can do, but if you want proper accuracy then you need to invest in dedicated sleep monitoring equipment as a watch on your wrist will never come close to electrodes on your head.
Ardently Apple devices and Oura are at the top in terms accuracy of what wearables can do, but if you want proper accuracy then you need to invest in dedicated sleep monitoring equipment as a watch on your wrist will never come close to electrodes on your head.
[1] https://www.youtube.com/@TheQuantifiedScientist