When comparing the best fitness trackers, sleep tracking is a core pillar to consider However, when testing various sleep tracking devices such as the Oura Ring, Fitbits, and even the Apple Watch, it can be difficult to determine from anecdotal evidence alone which wearables provide the most accurate data overnight

For those craving a more rigorous sleep tracking comparison, there is scientific evidence that one of these devices is more accurate than the others

Brigham and Women's Hospital, as part of a sleep tracking study against polysomnography (the “gold standard” of sleep assessment), brought the Oura Ring Gen 3, Apple Watch Series 8, and Fitbit Sense 2 to the lab in brought to the lab

According to the study, the Oura Ring had the highest sensitivity for detecting deep sleep at 795% compared to the polysomnography control; the Fitbit Sense 2 detected 617% and the Apple Watch Series 8 detected only 505%

The Oura ring also “did not significantly underestimate or overestimate any of the four sleep stages,” but the Apple Watch overestimated light and deep sleep by an average of 45 and 43 minutes, respectively (This is not entirely surprising, given that sleep stage information was only added to the Apple Watch's sleep tracking feature last year)

While these findings are certainly interesting, there is a rather serious snag: the Oura Ring Gen 3 was replaced by the Oura Ring 4, and the Apple Watch Series 10 launched in September

The Fitbit Sense 2 is still available new, but it is confirmed that this two-year-old watch will be the company's last product; Fitbitcom has officially closed, and Google is encouraging customers to buy the Pixel Watch 3 instead

In short, the findings should be taken with a grain of salt Still, there is no doubt that Oura is a step ahead when it comes to the sophistication of its sleep tracking data, and some of my colleagues have been found to have sleep apnea thanks to the Oura Ring Peer-reviewed studies often take longer to conduct and publish, but given the fast pace of progress in the health tracking technology market, it will be interesting to see the results with the latest devices

For example, the Oura Ring While this study sheds positive light on what we consider to be the best smart ring, accuracy should vary greatly between the Oura Ring 4 and the Oura Ring 3 Oura claims that in measuring SpO2, which is central to sleep tracking analysis, the new ring is up to 120% more accurate, it claims

So if you are in the market for a new sleep tracking device, the Oura Ring 4 is a wise choice