Fig. 3
Correlation between apnea–hypopnea index (AHI) and SpO2 Measures. a standard deviation of overnight SpO2 signal (SpO2 STD), b entropy of overnight SpO2 signal (SpO2 ENT), c below average burden (BAB), d average of normalized desaturation burdens of overnight desaturation episodes with ≥ 3% drops (ODB AVG), e standard deviation of normalized desaturation burdens of overnight desaturation episodes with ≥ 3% drops (ODB STD), f entropy of normalized desaturation burdens of overnight desaturation episodes with ≥ 3% drops (ODB ENT), g Overall nocturnal desaturation burden (NDB). h correlation values