Sleep tracker comparison

Quick note on a comparison I ran over the holidays on 4 (yes, 4 in parallel) sleep trackers: Oura, Firstbeat Lifestyle Assessment, Vital Scout, and the latest entrant, Beddr. Oura is a ring, Vital Scout a patch, Firstbeat uses a 2 lead ECG, and Beddr is a little pod that sticks to your forehead. Sounds weird, but it's quite comfortable and I did not notice it after a couple of minutes. Quick review of results from the night of December 25 / morning of December 26:

Beddr:

I'll have more to say later about overall Beddr UI etc., for now I'm just thinking about the actual output and mostly on the overall summary scores.

Vital Scout:

Oura:

Firstbeat Lifestyle Assessment:

And some info on the devices and how a few of them are worn:

The Vital Scout patch, in this pic the adhesive is already on the patch and you are looking at the three electrodes (which you can see through the hydrogel):

Here's me wearing the Vital Scout patch and the Firstbeat Bodyguard:

Finally the Beddr device and one of the adhesives:

What's really interesting is that the Firstbeat/Vital Scout and Beddr both seem to agree my sleep quality is poor / very poor (22 and 29 of 100 for Firstbeat and Vital Scout). Oura said it was quite good (89 of 100). I lump Firstbeat and Vital Scout together because the Vital Scout app relies on algorithms licensed from Firstbeat, so the only real difference there is due to data differences between the different measurement devices. There is one other difference that's a bit subtle that I will explain later. HRV compared reasonably well between Oura and the Firstbeat system (45 ms in Oura, 40 ms in Firstbeat), just based on the measurement tech the Firstbeat is definitely the more accurate.

I've been pretty happy w/ my Oura, but...I've also had reason to doubt whether I'm really sleeping that well. This comparison makes me more skeptical on their quality rating. Although the total time slept seems to align about as well as I'd expect with the others. Beddr seems to suggest I might have a sleep apnea problem. I'll dig into this a bit more in my next post.

BTW on the cycling front, I am now addicted to Zwift. Watch for me on there if you use it.