The beta opened up for registration in December, but filled up quickly and is currently closed to new sign-ups. The Fitbit Ionic is also compatible with the beta and is available to residents in the US, Australia, and UK.
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Each morning, after syncing my Fitbit with the Fitbit app on my phone, I would visit the Sleep Score beta website where a series of questions awaited. I was asked to rate my mood in the morning, how much energy I had when I woke up, and indicate if I had any alcohol, caffeine or worked out before falling asleep. There was an expanded set of questions that included more details about exercise habits for the previous day.
After answering the questions you are then shown the various metrics measured by the Sleep Score beta.
The quality of a night's sleep is scored on a scale of 0-100, with a score of 90 considered "excellent," and anything under 60 considered "poor." This is the most prominent section of the Sleep Score beta page and uses multiple points of data to provide a score.
There are three subcategories that are also scored: Sleep Duration, Sleep Depth, and Revitalization.
The first two are similar to what users currently see in the Fitbit app, comparing your goal of sleep duration to what you actually slept, as well as comparing your deep and REM sleep to what people of your age and gender should strive for.
Revitalization is a new category that takes into account any breathing disturbances and compares your daytime heart rate to your sleeping heart rate.
Fitbit hasn't clearly stated that the SpO2 sensor is being used to help score the Revitalization section, however, measuring the amount of oxygen in the blood is the best method at Fitbit's disposal to measure breathing disturbances.
One of the more intriguing aspects of the Sleep Score Beta is that in order for the Revitalization score to be accurate, you have to wear your Fitbit throughout the day. Otherwise, there's no heart rate or SpO2 data during the day to compare with your sleep data.
On days where I forgot to put on my Fitbit after getting ready in the morning or leaving it on the charger for an extended amount of time, my Revitalization score was noticeably worse than when I had the Fitbit all the time.
Another downside to the beta in its current state is that you're only able to view the past seven days of sleep scores. There isn't a method to view longterm sleep habits in an attempt to identify habits or trends.
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Granted, the program is released with the caveat that it's a beta and the company is surely working through which features to include, how much information to include, or how much it can include due to FDA regulations.
I would love to see the Revitalization score expanded upon and more information about what a score of 50 means; Was it really because I didn't have my Fitbit on all day, or is it because I showed signs of sleep apnea?
It's unclear how long Fitbit will keep the beta open, how the company plans on integrating the feature into its mobile app, or if it will remain a standalone service as it is right now.
I've found it useful to get a score each morning with the ability to break down the various metrics tracked by Fitbit. I can't wait to see what Fitbit does with the finalized version of Sleep Score and what actionable suggestions are able to be taken from long term trends.