Zeo vs Fitbit. Zeo incorrrectly shows...

published by Robert Richmond on Mon, 07/30/2012 - 12:48
English

 

Hi folks.   Here's an email I sent to Zeo support asking them to look into big inaccuracies in Zeo's analysis of my sleep compared to Fitbit and my own observations  (links to fitbit and zeo graphs at bottom).   Has anyone else seen REM mistaken for wake?

Note: I have observed this both with the table model and with the iPhone version.

 

 I’m trying to really analyze why Zeo is failing, so I bought a Fitbit, which also does sleep analysis, and used them both last night.   The two graphs are below.

This seems to be definitive proof that the Zeo is making incorrect conclusions, for four reasons:

1.Fitbit does not show the long periods of wake that the Zeo does, which I don’t remember in any way.

2.The Zeo says that at just after 2am, I quickly went from awake to deep sleep and back to awake again.   That’s not even possible.

3.I feel rested after a good night of sleep, and have done so every time the Zeo says I get a really bad night of sleep with being awake for several hours which I don’t remember.

4.I awoke several times last night from a dream, which I remember, but the Zeo only shows it once.  This happens a lot with the Zeo, especially in the morning final wake up.

I think what’s happening is that the Zeo is mistaking wake for REM.  It would explain all the differences.

Would you please pass this on to your developers?   Fitbit is really going to eat your lunch unless you can get this stuff fixed.  

And it is possible to fix it:  you need to give users a tool to reverse the wake to REM when they know that they were dreaming at certain points;  or at least have a slider bar to adjust the graph in that direction.  Call it “user normalization”.    Given your scientific basis of only 85% accuracy, that would seem to be a good thing to do for the 15%  of your audience that is getting bad results, or the 100% of your audience that is getting bad results 15% of the time.

Graphs:

fitbit:

http://www.brichmond.com/Zeo/fitbit7-23-12.jpg

zeo:

http://www.brichmond.com/Zeo/zeo7-23-12.jpg



 

 

Forums [fr:field:taxonomy_forums:forum:label]:

gwgaston

Tue, 07/31/2012 - 13:04

I also use a fitbit, but do not really use it for accurate sleep data. Only to log that time as 'sleep' and not just as 'inactive'. It cannot look at your brainwave patterns. While it has other parameters it looks at,  the movements you make dirrectly affect the times awake that are recorded by the fitbit device. I saw this as I had an avg of 8 times awake with the fitbit on my wrist, but when I moved the fitbit to my collar it went to avg of 3,. 

Neither of these devices appear perfect, but for sleep data I trust my Zeo for sleep data.

If you have had your fitbit for awhile, make sure to update the firmware. And if your sensors are over 3 months on the Zeo, get a 3 pack as well.

 

Bill Oliver

Thu, 08/16/2012 - 19:19

i'd used the Zeo over a year ago to monitor my sleep patterns.  I'd been diagnosed with sleep apnea and wanted to see if my sleep (or lack of) had anything to do with my fatigue during the day.  I'd always slept well with very few breaks in my sleep and the Zeo confirmed it.  I'd also had a sleep study about a month before where the EEG data showed that I had several periods where I was awake for very short periods (<15 seconds) during the night, none of which I remembered.  That clock stopped working and because I knew what was going on I didn't replace it for about a year.  About a month ago I bought another Zeo clock and started measuring again.  About the same time I came across the FitBit and bought it, but only for the 10,000 steps pedometer piece.  My understanding of the FitBit is that it measures movement.  From their website "The Tracker monitors how many times and how long you wake up during the night. Over time, you can apply what you learn to better understanding what helps you sleep better."   I couldn't find much more information than that. 

One thing I discovered about Zeo is that the headband can be a problem if it doesn't stay in place.  i'd like to see a different type of headband used.  I know there were nights when the results with Zeo were questionable only because the headband would slip around and when it started in the center of my forehead when I went to bed, in the morning it might be positioned just about anywhere.  As it happens, I have to wear a full face mask for the sleep apnea.  I put the  Zeo on first and then the CPAP mask which holds the Zeo headband in place rather well and the results I see are consistent from night to night.  I know that it says I wake up at night on occassion but with the exception of a few times I actually had to get up to go to the bathroom I don't remember them.  That's about the same results I had with the sleep study.  Also, I don't move much when I sleep.  I've used a night vision Cam on my laptop to record my sleep on a couple of occassions.  I literally sleep like a log.  The Zeo did capture my waking up but the Fitbit wouldn't because I didn't actually move.  None of this may explain why you're getting the readings you are but I'd suggest checking to make sure the headband isn't slipping.  Just based on how the FitBit is designed vs how the Zeo is designed I'd trust the Zeo more for accuracy. 

 

Robert Richmond

Sun, 08/19/2012 - 00:28

Yup, the fitbit only shows if your hand moves during the night.   The Zeo shows very LONG periods of wake for me, 2 or 3 hours at a stretch.  The fitbit and my memory say they didn't happen.   I think I would remember if I was awake for 3 hours in the night.  And I think I would move my hand at some point during those three hours!   

I've positioned the Zeo REALLY tightly to avoid exactly what you talk about, and it didn't slip at all.   It's somehow mistaking REM for wakefulness, which is a bummer.  I can't trust it.   It works on one of my kids, though.  He gets scores of 120 (deep sleep all night!).  I think I am just in the 15% of inaccurate results that they admit to (which means it's probably more).

 

I too was diagnosed with moderate to severe sleep apnea and used the C-PAP for awhile.  However, I bought an oxygen saturation finger cuff with USB out, and have used it during several nights.   It reports no de-sats.  I tested the thing during the day by holding my breath, and I got it to report de-sats, so I know it works.  Also I have recorded my snoring, and there are no short stops of breathing.  I am convinced that the sleep lab's result was bogus, and that there might be a scam going on in the sleep diagnosis business.   Getting a lot of people to buy $2000 C-PAPS is a pretty attractive proposition.

Mark Gordon

Sun, 08/19/2012 - 10:40

As a physician I stopped sending patients to the sleep study centers becuase everyone comes back as needing CPAP. I sent a family member to one of the University of California associated centers and they came back needing CPAP. What a great business...  Have the center send you a video of the patient and the corresponding wave patterns to support their claim.   Now you know why insurance is so high...

Brandis

Thu, 10/18/2012 - 02:22

Because I kept losing the headband (and I never really got used to it), I recently switched to ECG Electrodes and they really work great. I also heard from others that the data is more accurate with such electrodes. Maybe this would help for your problem as well.

BTW, I also have  the fitbit, and I found it never showed my sleep pattern very accurately, I have been told that I move very little during the night and sometimes, when I wake up in the morning, I keep laying in bed for a while, also not moving much, when the FitBit started vibrating (the wake-up alarm) at the latest time set and I looked at the sleep data, it showed me as being asleep up to the moment the alarm went off.

 

Robert Richmond

Thu, 10/18/2012 - 16:23

THanks for the tip, Brandis.  I found your other thread with Hypagog.   Did you get the electrodes from that link or somewhere else, and did you put them on as the picture showed?  Are there smaller ones?  I would love to get more accurate data now that my brain doesn't put out as much signal.

And Mark, thanks for your comment about the sham sleep studies.   Your expert view as a physician makes me feel less of a conspiracy theorist and more of just an observer!  Maybe there is some subset of patients for whom this is necessary, but it seems way overdiagnosed.   I admit to having been really scared by the diagnosis and felt like if I didnt wear the damn thing all the time I'd get heart trouble or alzheimers.