A new study has shown that Oura leads key competitors when it comes to the tracking of sleep stages.
The study assessed the accuracy of three consumer sleep trackers — Oura Ring Gen 3, Fitbit Sense 2, and Apple Watch Series 8 — by comparing them to the gold standard for sleep evaluation: polysomnography (PSG).
Thirty-five participants wore all three devices during a single-night inpatient study while also undergoing PSG monitoring.
Tested: Best sleep trackers
For detecting sleep vs. wake states, all devices performed well, and the test revealed a sensitivity of 95% or higher.
However, accuracy in detecting different sleep stages (light, deep, REM) varied:
- Oura Ring Gen 3: Sensitivity ranged from 76% to 79.5%, showing good agreement with PSG across sleep stages.
- Fitbit Sense 2: Sensitivity ranged from 61.7% to 78%, but it tended to overestimate light sleep and underestimate deep sleep.
- Apple Watch Series 8: Sensitivity ranged from 50.5% to 86.1%, underestimating wake and deep sleep while overestimating light sleep.
Wareable says
The results are interesting but pretty much confirms what we already know. Wearables can be very good at telling you how much sleep you have. We’ve tested all of these devices and would rate each one highly for accuracy.
But we already know that sleep staging data can be hit-and-miss.
Even Oura, which comes out top in this study, showed decent sleep staging accuracy – but far from perfect.
And as we have maintained for years, knowing how much REM sleep you got in a night isn’t that useful. Firstly, it isn’t actionable, so if you are getting poor deep sleep you have limited control over what you can do about it.
It’s more important to develop habits like good sleep consistency, and knowing your sleep chronotype and how sleep/wake times fit with your circadian rhythm.
The good news is…Oura is excellent at that stuff, too.