Table 2.

Mean (SD) values of measures in primary analysis including all participants (XeY denotes scientific notation).

Quarter	MPRa	MRRIb	SDNNc	RMSSDd	LFe	HFf	LHRg
Quarter 1	76.8 (10.8)	0.80 (0.113)	0.11 (0.035)	0.80 (0.113)	3.4e+3 (1.7e+3)	8.3e+3 (4.2e+3)	0.41 (0.04)
Quarter 4	75.8 (13.5)	0.81 (0.137)	0.11 (0.023)	0.81 (0.161)	3.5e+3 (2.1e+3)	8.5e+3 (5.3e+3)	0.42 (0.03)

^aMPR: median pulse rate (pulse beats per minute).

^bMRRI: mean R-R interval (seconds per pulse beat).

^cSDNN: standard deviation of R-R interval.

^dRMSSD: root mean square of successive difference of R-R interval.

^eLF: low-frequency power (ms²).

^fHF: high-frequency power (ms²).

^gLHR: ratio of LF to HF.