Table 4.

Results of the multiple linear regression for the three DTI metrics against the patient demographic information of patient age, the time from their concussion to the MRI scan (TTS), Post-Concussion Symptom Scale (PCSS) score and the interaction between TTS and PCSS score.

DTI Metric	Coefficient	Estimate	Std. Error	t-value	Pr (>|t|)
FA	Intercept	27.474	3.985	6.894	<0.001***
	Age	−1.362	0.239	−5.691	<0.001***
	TTS	−0.0281	0.0271	−1.038	0.311
	PCSS	−0.0809	0.0365	−2.214	0.038*
	TTS:PCSS	8.76 × 10−4	5.1 × 10−4	1.718	0.101
AD	Intercept	0.515	0.456	1.130	0.271
	Age	−0.0211	0.0274	−0.771	0.449
	TTS	−0.00223	0.00310	−0.720	0.480
	PCSS	0.00418	−0.205	0.839
	TTS:PCSS	2.53 × 10−5	5.83 × 10−5	0.433	0.669
RD	Intercept	32.923	2.419	13.609	<0.001***
	Age	−0.341	0.145	−2.344	0.0290*
	TTS	−0.0306	0.0164	−1.859	0.0771.
	PCSS	−0.0446	0.0222	−2.011	0.0573.
	TTS:PCSS	9.11 × 10−4	3.1 × 10−4	2.941	0.0078**

Note: Significance codes: 0 ‘***’; 0.001 ‘**’; 0.01 ‘*’; 0.05 ‘.’; 0.1 ‘ ’ 1. For FA: Residual standard error: 2.994 on 21 degrees of freedom. Multiple R-squared: 0.6409, Adjusted R-squared: 0.5725. F-statistic: 9.368 on 4 and 21 DF, p-value: 0.0001653. For AD: Residual standard error: 0.3423 on 21 degrees of freedom. Multiple R-squared: 0.07259, Adjusted R-squared: −0.1041. F-statistic: 0.4109 on 4 and 21 DF, p-value: 0.7988. For RD: Residual standard error: 1.817 on 21 degrees of freedom. Multiple R-squared: 0.4367, Adjusted R-squared: 0.3295. F-statistic: 4.071 on 4 and 21 DF, p-value: 0.013473.