TABLE 4.

Hierarchical multiple regressions of sociocultural predictors of total vocabulary score.

Block		B	SE	β	R2	Adjusted R2	ΔR2
1	Age	2.670	0.245	0.470***	0.221	0.219	0.221
2	Age	2.654	0.244	0.467***	0.231	0.227	0.010*
	Sex	−5.504	2.383	−0.099*
3	Age	2.630	0.243	0.463***	0.243	0.232	0.012
	Sex	−5.681	2.390	−0.102*
	Number of other children in household	0.829	0.887	0.042
	Number of adults in household	1.363	0.903	0.067
	Maternal education	2.955	1.709	0.102
	SES	−0.390	0.854	−0.027
4	Age	2.636	0.243	0.464***	0.252	0.238	0.010
	Sex	−5.491	2.389	−0.099*
	Number of other children in household	1.042	0.919	0.053
	Number of adults in household	1.152	0.905	0.057
	Maternal education	2.973	1.777	0.102
	SES	−1.226	1.040	−0.084
	Language	0.177	1.263	0.007
	Geographic area	6.630	2.895	0.116*

***Significance at the 0.001 level.

*Significance at the 0.05 level. Maternal Education scale: 1 = no formal schooling, 2 = primary school incomplete, 3 = completed primary school, 4 = high school incomplete, 5 = completed high school, 6 = post-school qualification. SES composite score based on maternal and paternal level of education, maternal and paternal employment status, household income, and household expenditure on food.