Respironics System One 60 series - data accuracy?

I just had my first follow up with my physician's PA. I'm doing well in my first month at 14cm pressure and I am feeling so much better now. While discussing the need for a full night titration study (I had an initial study that was a split study due to very high AHI - they put me on CPAP two hours into it) this person suggested that the data from this machine is useful only for compliance reporting. I find that hard to believe that the data that machine collects is really so inaccurate as to be discarded. There must be a statistical model that suggests where the data accuracy falls in relation to a full lab study. Just wondering what experiences and opinions on the data collection? I am guessing data collection and accuracy has improved over the years, and I am wondering if this PA is a little behind the times or if the data is really as unreliable as they indicated.

Exactly what model PR S1 60 series machine are you using? If unsure the model numbers ...3 digits ...are on the bottom of the blower unit.
There are models that only record hours of use...compliance and there are models that record full efficacy data.
If you have a model 260 or lower...you get only hours of use on that SD card
You need model 460 or higher to have any useful data and it is quite accurate.
I am wondering if your PA was referring to the model you are using as only offering compliance data.

It's a 460P. I had forgotten about that specific model number. And I've been pulling the data off the card since the first week expecting it was pretty accurate which you seem to be confirming. I'm wondering how much of that PA's comment was geared toward broaching the topic of a full titration study without alot of push back. I have a habit of double checking the prescriptions, looking at package inserts from medications, and so forth. The goals being 1) to avoid winding up unexpectedly dead and 2) getting the best care I can get. I may be looking for a new provider as the months go on since I am so far unimpressed with the overall situation. But I am feeling much better now and progressing with treatment and that's a pretty good status quo in my book

There are only two areas of inaccuracy with respect to Respironics System One machines.
1) The clock tends to drift so the exact time will be a little iffy. You can get a handle on this by making an accurate time check when you turn the machine on and comparing that time with the time reported on the machine.

2) In the summary data, the values for Tidal Volume and others are rounded off in an unusual manner. You can correct this rounding by turning your machine on in the evening, waiting about one minute, turning it off, and then turning it back on. That forces something in the Encore software to recalculate and then report to the nearest 1/10th.

Beyond those very small items, the machine reports accurately and both of my sleep doctors accept the data as diagnostic. Sounds like typical BS to put the patient into place because "I'm the professional and you can't possibly understand."

Just ignore such comments and watch your own data.

Thanks for the information and the responses Pugsy and JDS74, they pretty much confirm what I suspected from the beginning. Even though my insurance carrier provides for one titration study per year, and at least one additional under certain circumstances. In some cases I am paying substantially out of pocket for these services and I am willing to ask questions when I have them. If I don't like the answers I can always move on.

JDS74 wrote: ... 2) In the summary data, the values for Tidal Volume and others are rounded off in an unusual manner. You can correct this rounding by turning your machine on in the evening, waiting about one minute, turning it off, and then turning it back on. That forces something in the Encore software to recalculate and then report to the nearest 1/10th.

I just did another experiment.
After just letting the machine run all night without interrupting and downloading the data to Encore Pro, the values that I track were:

PTB% 85.0%
AHI 8.6
BPM 16.0
Vt 680 mL
Hyp 5.3

Then I hooked up again for two minutes (fully awake) and got the following values:

PTB% 85.1%
AHI 8.6
BPM 16.0
Vt 682.4 mL
Hyp 5.3

Notice that the PTB% and Vt values seem to be either truncated or rounded down. With one experiment, I can't really tell which. I hope to get an example with the "unrounded numbers" lower afterwards indicating a rounding rather than truncation. If the values after are always higher (for example Vt goes from 680 to 688), then truncation is indicated.

In either event, an interesting programming choice.
Film at 11:00