Table 3.

Association of birth <26 weeks with the change in diffusion parameters in white and gray matter regions of interest in a multivariate model including terms 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
Birth at < 26 weeks	0.023 mm2/sec	− 0.006 to 0.051	0.12	− 0.01	− 0.018 to − 0.003	0.008
Moderate-Severe Brain Injury	0.03 mm2/sec	0.003 to 0.058	0.03	− 0.012	− 0.19 to − 0.005	0.002
Model including additional terms for days of mechanical ventilation, PDA, and NEC:
Each week increment in PMA				0.008	0.007 to 0.009	<0.0001
Birth at < 26 weeks				− 0.002	− 0.02 to 0.004	0.53
Moderate-Severe Brain Injury				− 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
Birth at < 26 weeks	−0.013 mm2/sec	−0.03 to 0.005	0.16
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.