The purpose of physiologic calibrations is to:

The purpose of physiologic calibrations is to:

• A. Establish certain scoring references for the sleep study
• B. Confirm the integrity of the signals
• C. All of the above
• D. Verify signal derivations for each channel

Answer: (C)

Physiologic calibrations establish the reference levels and ranges that scoring relies on, so the thresholds used to categorize sleep stages and events are consistent and meaningful. They also verify that the equipment is working correctly by checking signal integrity, including proper impedance and absence of unexpected artifacts. In addition, calibrations confirm that each channel’s signal derivations (the montages and references used to derive EEG, EOG, EMG, etc.) are accurate, so what you see reflects the intended measurements. Because calibrations ensure both accurate scoring references and clean, correctly derived signals, they address all the necessary aspects of data quality in a sleep study.

Physiologic calibrations establish the reference levels and ranges that scoring relies on, so the thresholds used to categorize sleep stages and events are consistent and meaningful. They also verify that the equipment is working correctly by checking signal integrity, including proper impedance and absence of unexpected artifacts. In addition, calibrations confirm that each channel’s signal derivations (the montages and references used to derive EEG, EOG, EMG, etc.) are accurate, so what you see reflects the intended measurements. Because calibrations ensure both accurate scoring references and clean, correctly derived signals, they address all the necessary aspects of data quality in a sleep study.