Table 3. Estimated Cognitive Scores in Children With and Without Brain Injury at Different Points.

Variable	No Brain Injurya		Brain Injuryb
	Cognitive Score, Mean (95% CI)	P Value	Cognitive Score, Mean (95% CI)	P Value
Cognitive score at 18 moc	102.2 (96.3 to 108.2)	.001	97.2 (89.1 to 105.3)	.001
Cognitive score at 36 moc	99.7 (93.7 to 105.7)	.001	94.2 (86.1 to 102.4)	.001
Cognitive score at 4.5 yc	99.5 (93.5 to 105.5)	.001	94.2 (85.9 to 102.5)	.001
Gestational age (centered at 28 wk)	1.3 (0.5 to 2.1)	.002	0.3 (−1.3 to 1.9)	.69
Maternal education
Primary or secondary schoold	[Reference]	[Reference]	[Reference]	[Reference]
Undergraduate degreed	2.0 (−4.3 to 8.3)	.54	5.6 (−3.6 to 14.8)	.23
Postgraduate degreed	7.4 (0.01 to 14.8)	.05	13.7 (2.2 to 25.1)	.02

^aThe group with no brain injury included 344 observations and 124 patients. Log likelihood = −1321.17; P = .001.

^bThe group with brain injury included 170 observations and 62 patients. Log likelihood = −648.38; P = .001.

^cMean (95% CI) of the cognitive scores at each occasion.

^dAssociated increment in cognitive scores with maternal level of education.