Search Support Database

Events and time periods included in the Analysis Duration/Total Recording Time and Total Sleep Time

 Analysis Duration/Total Recording Time (TRT)

The Analysis Duration is the same as the total recording time (TRT), i.e., the duration from Analysis Start to Analysis Stop. The TRT includes periods of Wake.

Events within Analysis Start and Analysis stop are included in analysis/reports, but events outside of Analysis Start and Stop are excluded.

Events scored within signal artifacts are included in analysis/reports (low signal quality or in movement). This is part due to the patient’s movement (twisting and turning) before, during or, after a respiratory event and or limb movements. Therefore events during these periods must be included when calculating the AHI. For excluding events within artifacts, Invalid Data needs to be scored (select event > right click on the mouse, Score Event > Signal > Invalid Data).


Total Sleep Time (TST)

TST is the total time where the patient was sleeping (based on manual scoring or automatic Sleep Staging). Events during periods scored as Wake (select event > right click on mouse, Sleep Stage > Wake) are excluded from analysis/report.

For recordings where no sleep stage or sleep type events (from manual scoring or automatic Sleep Staging) have been scored: Estimated Sleep Time (Same as AASM term Monitoring Time) is the parameter used for analysis. The Estimated Sleep Time is the time the patient is lying down during the recording. Periods of Unknown positions are included in the Estimated Sleep Time and events during Unknown positions are included in analysis/reports. For Estimated Sleep Time, events scored within Upright position (>53.33°) are excluded from analysis/reports as it is assumed that the patient is awake during Upright Position. To account for patients who sleep in reclining chairs (Lazy Boy) or adjustable beds (Posturepedic or hospital bed) the Upright Position can be changed to Unknown Position and or an Analysis can be created to include the Upright Position (90°) in which both scenarios would be included in the Estimated Sleep Time.

*Please note that not all features or all products are available in all markets. Our products are medical devices and subject to registration/approval in each market area. For more information on product availability please contact

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