Table 2.

Dimension reduction of frequency-domain features of the FHRV.

Frequency-Domain Features	Principal Components
	1	2	3
VLF	0.903	0.345	−0.013
LF	0.238	0.932	0.132
HF	0.275	0.802	−0.443
Total power	0.862	0.465	0.001
SVB	−0.085	0.286	0.939
%VLF	0.809	−0.566	−0.089
%LF	−0.788	0.573	0.172
%HF	0.238	0.932	0.132

Correlations > 0.80 highlighted in bold.