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Ric wrote:The two graphs in question are not actually inconsistent. Since there are no OAI events with pressures greater than 9 recorded in the first week of 2006, that tells me that the 10-12 cm pressure events occurred in the last 2 weeks of Dec 2005. The OAI at pressures 10, 11, 12 (40, 26, 30 respectively) are RATES, and not a raw tally for any given day. There's no point in looking for a peak of 40 for any given day on the OAI-HI vs date graph.

Here's a hypothetical: say there are 10 OAI events during a 15 minute period on any given day which were resolved at 10 cm-H2O pressure. That represents a RATE of 40 events/hr. If that were the only time spent at that pressure, then that is what you would see on the OAI vs. PRESSURE curve. The actual number you see there represents all the OA events at that pressure divided by the total cumulative hours AT THAT PRESSURE.

Now to complete the calculation, bring up yet another graph, under the "HOURS" tab. It shows the cumulative time spent at a given pressure. That is the denominator in the RATE calculation, that is, the OAI. Unfortunately there is no chart or graph in either EncorePro or MyEncore that shows the cumulative EVENTS at a given pressure. You could arrive at this rather tediously if you wanted to look at all the DAILY detailed reports in EncorePro that shows the OA and H events juxtaposed with the pressure graph. Or if you trust the RATE graph in MyEncore you could calculate it backwards by multiplying the OAI times the cumulative hours, although in this case it doesn't prove anything since that is a completely circular argument. But that would tell you what the numerator OUGHT to be. Nevertheless, I am willing to believe the graphs you displayed are not really inconsistent. It's a matter of understanding what they trying to convey.

george49 wrote:And the machine will only put out 20 so i really don't understand it. Maybe some one can but some light on it.

The machine you are describing will deliver up to 20 cm-H2O pressure. I think that is the "20" that you are referring to. But there is no limit to the number of OSA events you can have at a given pressure. It will record as many as you can throw at it. And likewise there is no limit to the RATE that derives from those events, depending on how FAST you can throw them at it. That's entirely up to you.

Hope that helps.