ECG	Electrocardiogram
HR	Heart Rate
HRV	Heart Rate Variability
IMU	Inertial Measurement Unit
LoA	Limits of Agreement
MAE	Mean Absolute Error
MRE	Mean Relative Error
PPG	Photoplethysmography
PSD	Power Spectral Density
QI	Quality Index
SmartEW	Smart Eyewear “Essilor Connected Glasses”