Table 1. Mean demographic characteristic of the LRC and HRA infants (SD).

	n	LRC	n	HRA	t(df)	p
Infant’s birth weight	26	7.9(1.2)	28	7.9(0.9)	0.10(52)	0.92
Mother’s age at infant’s birth	26	33.6(4.4)	28	34.9(4.8)	−1.05(52)	0.3
Father’s age at infant’s birth	26	36.3(4.5)	28	38.2(5.9)	−1.34(52)	0.19
Mother’s education level	19	6.5(1.43)	24	5.7(1.6)	1.63(41)	0.11
Father’s education level	19	5.9(1.51)	22	5.1(2.04)	1.50(39)	0.14
Family income	19	7.4(1.61)	24	7.4(1.25)	−0.11(41)	0.91

Note that not all families provided all demographic data.