Table 2.

Descriptive HRV values for concussed (n=29) and control (n=15) participants at baseline

HRV variable		Mean (SD)	25th percentile	50th percentile	75th percentile
SDNN	Concussed	206.61 (62.04)	156.76	185.85	245.78
	Control	194.05 (55.00)	156.42	198.36	223.63
RMSSD	Concussed	74.48 (30.94)	53.29	70.39	77.65
	Control	78.63 (31.95)	59.68	75.85	101.61
pNN50	Concussed	27.51 (10.63)	20.36	25.27	33.43
	Control	31.12 (12.88)	26.49	32.51	37.42
HF	Concussed	556.77 (373.28)	211.59	559.71	604.17
	Control	560.23 (352.01)	291.40	546.28	602.64
HFnu	Concussed	36.91 (9.60)	29.98	34.21	45.28
	Control	41.53 (9.10)	30.22	37.08	45.2
Mean HR	Concussed	77.01 (4.38)	71.84	74.72	81.49
	Control	75.99 (9.28)	70.29	74.97	80.36

HRV, heart rate variability.