Is the Nox T3 a valid test?

[gaydolphinorgy]

Can it reliably test for UARS/SDB? My doctor wants to use it.

https://noxmedical.com/noxt3s/

[desaturator]

I'm suspicious of all these commercial sleep study devices but, really, what choice to do we have at present? In the UK, at least, full-scale lab-based testing seems to have become a thing of the past. Many of these home devices use technologies that have primarily been validated by studies funded by the manufacturers and their investors. They often have a vested interested in over-diagnosing sleep disorders, because they are connected with businesses that make treatment equipment.

I think this is a deeply concerning situation, but we don't seem to have much alternative to using these devices.

[Ratchick]

Nothing is going to be exactly the same as full polysomnography (i.e. a sleep test in a hospital with EEG etc and a clinician watching you sleep) but the hospital home tests are close enough for these purposes - they at least come with a band around the belly and chest to measure for movement and make it easier to diagnose centrals properly. They DO still do inpatient sleep studies, but for something like suspected apnea, they usually go with a home study first rather than waiting months for a sleep study room to be available. The problem is right now that the NHS is overwhelmed (particularly after the last two years) after years of the Government deliberately underfunding it while trying to subtly dismantle it and make it more like the US system, which honestly, terrifies me.

That said, The Nox looks like it does actually use a belly and chest belt, as well as a nasal cannula to measure breath flow and a pulse oximeter. This should be enough to get the information you need for a diagnosis. The only thing it seems to be estimating is sleep stage without the use of EEG. This might be an issue to diagnose other sleep disorders where the exact stage of sleep is important, but for something like SDB/Apnea, it shouldn't be a huge issue.

Honestly, the reliability is far more down to who is reading the data and who isn't. I don't actually know the specific device that I had, but it looked similar to this, and it accurately diagnosed my central sleep apnea when the hospital specialists read the data. As long as they're familiar with what UARS looks like, then there's no reason they shouldn't be able to diagnose it from one of these kinds of tests.

Now, Watchpat tests? That's a whole other thing. That doesn't measure your breathing flow directly, or any measure of breathing effort. It bases all of its data on oxygen saturation, pulse and peripheral arterial tone. That, at best, gives you a decent estimate of OSA. But it's going to miss a lot of stuff by not measuring directly.

[kappa]

I agree with Ratchick. The Nox T3 is a Type III test but appears to be better than most type III test systems, given that it has both chest and abdominal effort straps and 2 optional ExG (EEG, ECG, or EMG?) inputs. I had a Type II home sleep test using a Nox unit (similar to A1 but older version) and was wired up with around 12 electrodes so likely similar data quality to an in-lab test.

I would speculate that a UARS diagnosis would be based off effort strap and flow rate data which are both directly measured by the T3 so it is likely an adequate test.