Repeatability of Titration Tests

Has anybody seen studies on the repeatability of titrations tests? I went back to the sleep clinic after a year and a half for a retest as I was still not feeling "refreshed" in the morning. The tech said I needed my setting raised to 9 from 6. After 2 weeks of air blowing out my mouth, I called the clinic and explained my situation. They said they hadn't analyzed my data yet but should get to it tomorrow. Low and behold I really didn't need the pressure at 9 and in fact 5 would be OK. How is that? I am going to adjust the pressure down and try some of the methods mentioned here to keep my mouth shut. Otherwise I guess I am going for the full face mask. I have been reasonably happy with the Resmed Swift nasal pillow.

However, I am curious if you did a test several times over a month lets say would you get the same result?

Don't see why not. Barring any changes in you.

Can't say that I've seen studies regarding reliability, but I do think that results might vary greatly from one night to another, and/or from one sleep study center to another. This posting provides an example:
http://www.sleepnet.com/noncpap19/messages/488.html
This is why I prefer my auto-titrating machine--my pressure needs vary somewhat night to night (and throughout the night!), and the auto machine seems to do a great job of addressing those changes.

You may want to have copies of all those studies to lay side by side and compare. This should include the titration info on the different pressures, how long at each, and how many events at each level. Should also tell your position and sleep stages. Maybe there will be some clues as to the differences. A successful study will capture what is considered a worse case scenario, which is generally considered in REM and supine. If that didn't happen in one and did another, that's just one possible cause of differences. A couple of my reports say the test was suboptimal because of failure to record while in REM and supine. Looking at your data comparatively in black and white will either resolve your anger or substantiate it. Or you can move forward from here.

Well, we don't sleep the same every night, even at home. But now that I can FINALLY sleep during an in-lab titration I think it would be INTERESTING to have the money to be able to have 7 consecutive nights of in-lab titrations by 7 different RPSGTs at 7 different sleep labs and hopefully even w/as many different PSG software as possible. And then compare the results.

I do agree we don't sleep the same each nite.
I've had 3 titrations in 2yrs. Two came up within 1cm. The last is pending Govt. approval (takes no less than 4 weeks at VA).

The only diff I've seen so far is the application of the determined pressure. Going from CPAP (17) to BiPap (18/15) made all the diff for me. Even going from Straight cpap to an auto made a big improvement for me just didn't help me exhale at 17-20cm.

If you can't exhale are you breathing? (NOT).

Certainly the variable(s) from nite to nite are "us". What we ate, drank, sleep position, and how we crimp our neck or open our mouths, to name a few.