. 2014 Sep 1;31(17):1457–1477. doi: 10.1089/neu.2013.3171

Table 3.

DTI Region-of-Interest (ROI) Analysis: Group Differences in Presence of One or More Abnormal ROIs among CT/MRI-Negative mTBI, CT/MRI-Positive mTBI, and Control Subjects

	CT/MRI-negative mTBI (no acute traumatic intracranial abnormality or depressed skull fracture on CT or conventional MRI) (44 subjects)	CT/MRI-positive mTBI (positive acute traumatic intracranial abnormality and/or depressed skull fracture on CT and/or conventional MRI) (32 subjects)	Controls (50 subjects)
	Number of subjects (proportion of subjects)	Number of subjects (proportion of subjects)	Number of subjects (proportion of subjects)
One or more ROIs with FA more than 2.2 SDs below control-group mean	11 (25.0%)^a,b	14 (43.8%)^b	5 (10.0%)^a
One or more ROIs with FA more than 2.2 SDs above control group mean	8 (18.2%)^c	5 (15.6%)^c	8 (16.0%)^c

^{^a,b,c}

Each superscript denotes a subset of participants whose column proportions do not differ significantly from one another, by Pearson's χ² test with p < 0.05. Row 1: There was a statistically significant difference between CT/MRI-positive mTBI (43.8%) and control subjects (10.0%), with one or more ROIs with FA more than 2.2 SDs below the control group mean (p = 0.0006). There was no significant difference between CT/MRI-negative mTBI patients (25.0%) and controls (10.0%; p = 0.06). There was also no significant difference between CT/MRI-positive (43.8%) and CT/MRI-negative mTBI patients (25.0%; p = 0.14). Row 2: There was no significant difference among the proportions of CT/MRI-negative mTBI (18.2%), CT/MRI-positive mTBI (15.6%), and control subjects (16.0%) with one or more ROIs with FA more than 2.2 SDs above the control group mean (p = 0.96).

DTI, diffusion tensor imaging; ROI, region of interest; CT, computed tomography; MRI, magnetic resonance imaging; mTBI, mild traumatic brain injury; FA, fractional anisotropy; SD, standard deviation.