Table 1.

Research paper associated with HRV detected using an ECG, type of study, results of HRV, concepts being analyzed.

References	Features	Application	Modality	Notable results	Method of analysis
Rosenberg et al. (6)	LF, HF, LF/HF	1D/2D stress study	ECG	2D accuracy 90%	2D scatter plot.
Blood et al. (7)	LF, HF, LF/HF	Depression	ECG	HRV decreases	Frequency Domain
Molina et al. (8)	RMSSD, LF	Posture	ECG	HRV Reduced	Time Domain
Leti and Bricout (9)	RMSSD, LF	Overtraining	ECG	SNS Dominant	Time, Frequency
Walker et al. (10)	SDNN, HF	Noise	ECG	HRV Reduced	Time, Frequency
Wang et al. (11)	R-R, LF/HF	CHF	ECG	100% acc	SVM, KNN
Huang et al. (12)	LF, HF	Anxiety	ECG	HRV Reduced	LF, HF
Pinheiro et al. (13)	LF, SDNN	MI	ECG	HRV Reduced	Frequency Domain
Toni et al. (14)	LF/HF, LF, HF	CVD	ECG	HRV Reduced	Frequency Domain
Shi et al. (15)	HR, SDNN	Emotion	ECG	LF/HF inc	Time, Frequency
Ponnusamy et al. (16)	RMSSD, HF	Seizure	ECG	HRV Reduced	Time, Frequency
Howells et al. (17)	HF	Bipolar	ECG	HRV Reduced	HF
Rios et al. (18)	R-R, RMSSD	Drowsiness	ECG	HRV Inc	Time Domain
Jung et al. (19)	RMSSD, HF	Fatigue	ECG	HRV Reduced	Time, Frequency
Rahim et al. (20)	LF, HF, LF/HF	Drowsiness	ECG, PPG	HRV Reduced	Frequency Domain
Georgiou et al. (21)	RMSSD, HF	Exercise	ECG, PPG	91–99% acc	Time, Frequency
Gontier (22)	LF, HF, LF/HF	Mind Wander	ECG	LF dec	Time, Frequency
Vicente et al. (23)	LF, HF, LF/HF	Drowsiness	ECG	98% spec	LDA
He et al. (24)	ApEn, LF	Stress	ECG	17.3% err	CNN
Schmidt et al. (25)	LF, HF, ST	Stress	ECG, GSR	80% (3 labels)	Adaboost
Cho et al. (26)	SCL, LF/HF	Stress	GSR, PPG	95% acc	KELM NN