Table 2.

Association of gestational age (as a linear variable) at birth with the change in diffusion parameters in white and gray matter regions of interest in a multivariate regression model accounting for post-menstrual age (PMA) at scan, region of interest, and an interaction term to account for the two sites.

White Matter	Mean diffusivity			Fractional anisotropy
	Mean Change	95% CI	p-value	Mean Change	95% CI	p-value
Each week increment in PMA	− 0.021 mm2/sec	− 0.24 to −0.018	<0.0001	0.008	0.007 to 0.009	<0.0001
GA as a Linear Variable	0.002 mm2/sec	− 0.003 to 0.008	0.8	0.0009	− 0.006 to 0.003	0.2
Moderate-Severe Brain Injury	0.03 mm2/sec	0.003 to 0.058	0.03	− 0.012	− 0.19 to − 0.005	0.002
Gray Matter	Mean diffusivity
	Mean Change	95% CI	p-value
Each week increment in PMA	−0.018 mm2/sec	−0.02 to −0.016	0.001
GA as a Linear Variable	0.003 mm2/sec	−0.0001 to 0.007	0.06
Moderate-Severe Brain Injury	0.012 mm2/sec	−0.009 to 0.033	0.28

All models include terms for post-menstrual age (PMA) at scan, region of interest, and an interaction term to account for the two sites.