Huawei Band 4 (30 USD) VS Fenix 6x Pro (750 USD) VS Medical SPO2 Device

Ryu said:

I think it shouldn't be too hard to edit the algorithm as just increasing it around %4.

That won't work.  I just checked mine and that would put me at 102%.  Did you wear your other Garmin watches the same way your wearing your F6 in the video? 

Ryu said:

I think it shouldn't be too hard to edit the algorithm as just increasing it around %4.

There's an assumption here that everyone has a reading that is 4% low. What does that mean for those for whom Pulse Oximetry using wrist based sensors works?

I just know I'm going to get slammed for this but the results from wrist based sensors, whether for pulse oximetry or heart rate, are highly individualised. That's as much due to individual physiology as Garmin's technology.

So in truth you have 102%

I turned this feature off. It is useless in my opinion because it is so off. I had it on whole day and I started to even worry about my sleep as the measurements were down to 85%. But then I realized that during the day I would get anywhere between 90 and 98% within 1min. Slight move of the watch would throw it off a lot! My day average was maybe 95 or so but then I compared it with what my phone measured from a finger and phone was always between 98 and 100% during the day. I even think that the latest update made things worse in my case.

In summary, Garmin's blood oxygen level measurements are both inaccurate and imprecise.

On top it uses a lot of battery so it is a feature that I just ignore.

Just faking the numbers to make them beautiful probably isn't the best idea ;-)

Yes, i know. Those are not medical devices and should have some tolerance value and the results may vary individually. But i don't have any problem with wrist HR performance and i'm content with it even for my weight lifting workouts. The only problem for me is the pulse ox readings. It both takes too long to measure and is tended to have low results. 

I shaved my wrist hair to have more accurate results but it doesn't work. I try it on my both wrists and also try my watch on my sisters wrist and the result doesn't change; always inaccurate around %4. Moreover, Huawei Band 4 which is by far a cheaper device makes nearly %100 accurate readings.

Dr Phil said:

I just know I'm going to get slammed for this but the results from wrist based sensors, whether for pulse oximetry or heart rate, are highly individualised. That's as much due to individual physiology as Garmin's technology.

Having worked with medical pulse oximeters for several years, and now carrying one whenever I do stuff at higher altitudes, IMO the pulse ox sensor on these watches is pretty inaccurate. I think it's a function of transmitted light through lots of perfused tissue with a real monitor, vs the sending and receiving part being on the same side, flat on the skin. For the vast majority of younger people healthy enough to have a fitness watch, at rest, at reasonable altitudes <6000 feet, the oximeter should read 96-99%. As you get around 60ish and up, all bets are off. When I'm getting readings of 80% in sleep (I do not have sleep apnea), I know it's artifact and not a true reading. Sure, sometimes its because you have bad circulation to your hand/arm when sleeping, but I've also seen 90-91% while awake, at rest, and motionless -- and that's a nonsense number.

It would be interesting if the Huawei Band says 99%, if the medical device says 96% or less.

Just because it shows 99% does not mean it is accurate. That is not how accuracy is tested...

I think there may be something wrong with your Fenix.

My gf has a Huawei Band 4 PRO(same exact spo2 sensor as the band 4) and we just compared our pulse ox 3 times in a row. Twice we matched and the third time we were off by only one digit. 

I have tested my fenix 6 pro with a medical spo2 finger device when I first got it and was matching it with 90-95% accuracy.