Table 1

Mean ApEn differences for COP AP time series between days in athletes who had no evidence of postural instability after injury

Group	Condition	Mean difference between days	SE	95% Confidence interval for difference
Group	Condition	Mean difference between days	SE	Lower bound	Upper bound
Athletes were tested at preseason and within 48 h after concussion. Healthy subjects were tested on 2 separate days approximately 24 h apart. SE, standard error of the mean. Negative values indicate that scores declined from the first day to the second day.
Concussion	1	−0.142	0.050	−0.241	−0.042
	2	−0.130	0.042	−0.213	−0.047
	3	−0.083	0.053	−0.189	0.022
	4	−0.068	0.042	−0.153	0.016
	5	0.020	0.029	−0.038	0.079
	6	0.031	0.037	−0.043	0.105
Healthy	1	0.056	0.047	−0.038	0.151
	2	0.009	0.039	−0.070	0.088
	3	0.012	0.050	−0.087	0.112
	4	0.026	0.040	−0.054	0.106
	5	0.036	0.028	−0.020	0.091
	6	0.022	0.035	−0.048	0.093