Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account

New Posts   Today's Posts

Event flagging - How it is performed.
I am interested in how events are flagged.

Are the events flagged in the machine or the software (such as Sleephead) or both individually?

Do all machines calculate and flag the events identically? - Meaning, if same data was applied to all machines, would the scores be identical (or are some machines more or less sensitive in their flagging, resulting in slightly different numbers)?

Are there a certain standard set of rules that are used in flagging the events?

Just curious if everyone on the forum is comparing apples and oranges, or should you only compare your results with your own on the same machine.

Is machine (or software package) X more likely to flag a central event than machine (or software package) Y - from the exact same breathing pattern.

I bring this up, because some of the flagged patterns look pretty subtle visually, but each company's software may recognize them differently. I also seem to get a lot of "trash" events flagged while falling asleep and waking up (ie. I am awake and they are not officially "sleep" apnea), but they are part of the final calculated value sent to my doctor.

Post Reply Post Reply
The machines score the events. I believe that the manufacturers try to stick as closely as they can to the rules for scoring events that the Sleep Association publishes. I also think that the area where one sees the largest differences in how the machine flags events is in their discrimination between Obstructive Apneas and Central Apneas.

Hypopneas are an area where there is a fair amount of wiggle room in the definition for scoring them and the manufacturers can pick their own set of rules within the definition. As soon as I started using my Resmed S9 machine (prior machine was S8 version of the same machine) my hypopnea events reduced substantially. Resmed had altered their rules for scoring hypopneas.

Leak rate is another more obvious source of difference.

Best Regards,


Post Reply Post Reply

Possibly Related Threads...
Thread Author Replies Views Last Post
  One 45-minute hypopnea event aconcepts 3 245 04-08-2017, 04:24 PM
Last Post: Sleeprider
  Sleep event indexes Jihadhakim 3 170 03-29-2017, 10:05 PM
Last Post: Beej
  A new wrinkle--big CSR event dclaryjr 44 2,279 08-25-2016, 09:29 PM
Last Post: dclaryjr
  Please Help Analyze My Data (Pause Event) SkinTone 5 529 08-06-2016, 10:55 AM
Last Post: SkinTone
  Why is Flow Limit very low for OA event? Ed1101 7 856 03-26-2016, 05:54 PM
Last Post: palerider
Question Question about event flags in SH Jim Bronson 8 912 03-09-2016, 03:48 PM
Last Post: I_will_never_sleep_again
  Apnea event durations stanleydean 13 1,303 02-22-2016, 01:51 PM
Last Post: JAR14

Forum Jump:

New Posts   Today's Posts

About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.