SHHS Polysomnography DB: Annotation files

Annotation files

Use the PhysioBank ATM (or any PhysioToolkit application) to read the annotation files included in the SHHS Polysomnography Database. The text strings associated with each annotation are described below.

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Hypnogram (.hypn) annotations

The text strings indicate the sleep stage for the following 30-second epoch, according to this scheme:

codemeaning
Wsubject is awake
1sleep stage 1
2sleep stage 2
3sleep stage 3
4sleep stage 4
RREM sleep

EEG arousal (.arou) annotations

The text strings contain the following information:

Respiratory event (.resp) annotations

The text strings contain the following information:

Oximeter artifact (.oart) annotations

The text strings contain the following information:

Composite (.comp) annotations

The composite annotation file for each record contains all of the annotations in the .hypn, .arou, .resp, and .oart annotation files. These can always be distinguished by the event type (or sleep stage, in the case of the .hypn annotations). In addition, the chan field of the annotations, which appears in the fifth column of rdann's output, indicates the source of each annotation, according to this scheme:

codemeaning
0sleep stage (.hypn)
1EEG arousal (.arou)
2respiratory event (.resp)
3oximeter artifact (.oart)

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