Why is calibrating the mechanical baseline important in PSG?

Calibrating the mechanical baseline in polysomnography (PSG) is crucial for ensuring accurate sleep staging. The mechanical baseline serves as a reference point for the various physiological signals recorded during the sleep study, such as brain waves, eye movements, and muscle activity. When the baseline is properly calibrated, it enhances the clarity and reliability of the recorded signals, allowing for more precise identification of different sleep stages.

Inaccurate or uncalibrated baselines can lead to misinterpretation of the data, which could result in erroneous sleep staging. For instance, if the baseline is not set correctly, it may be difficult to distinguish between different sleep stages such as REM and non-REM sleep, potentially leading to an inaccurate assessment of the patient's sleep patterns and disorders. Hence, the importance of this calibration directly ties to the quality of sleep staging and ultimately impacts the overall evaluation of the patient's sleep health.