jnk wrote:No home machine overscores or underscores. The machines give estimates of AHI based on how each brand chooses to calculate its own estimates. So you can't compare your home-machine numbers to the numbers from a PSG or to numbers from another brand of machine. The numbers from home machines are given, not to be compared to your PSG numbers or other machines, but to be used as trending data to see if you are improving or worsening over time, or to see if an adjustment of pressure or comfort settings helps or hurts your therapy.
It is good with any brand of auto to set the lower number within a cm or two of what you need to get rid of apneas.
It is often thought that with a ResMed machine you pay more attention to your AI number than to your HI number or your AHI number. Getting AI below one on a ResMed is generally considered decent therapy. Tweak pressure for low AI before seeing if you can tweak down HI or AHI.
ResMeds are fine for self-titration and auto-titration above 10 cm as long as your snores and flow limitations fit the standard profile of what the machine is looking for in its prevention of apneas. If you have nonstandard snores and flow limitations, obstructive apneas may not be well-prevented by the algorithm, and you would then need to raise minimum pressure to deal with that for optimal therapy.
At least, that's one Internet-addicted opinionated guy's take on it.
jeff
Adding another 0.2 cents worth.
What JNK has said here is about as spot on as one can get. It is worth repeating that the Resmed S8 *does not overscore anything* it scores *exactly* the same breathing but scores it differently to some other brands. It is unfortunate that this was used as some kind of implied criticism of the Resmed algorithm for many years. The fact is all the major brands did a pretty good job in the period these machines were on the market.
JNK said "but to be used as trending data to see if you are improving or worsening over time" and that is the wisdom in his post.
Yes, the S9 changed the scoring to be more in line with how other brands scored the data but that move changed nothing other than incorrect perceptions.
DSM