. Author manuscript; available in PMC: 2011 Jan 12.

Published in final edited form as: Sci Stud Read. 2007 Feb 1;20(1-2):51–75. doi: 10.1007/s11145-006-9018-x

Table 4.

Genetic and environmental influences on grade 2 vocabulary and reading skills.

	A1	A2	A3	A4	a²
Boston Naming	.67^*				.45 (.34–.58)
Word Recognition Latent Trait	.30^*	.85^*			.81 (.69–.87)
Decoding Latent Trait	.32^*	.77^*	.30^*		.78 (.65–.86)
Woodcock Passage Comprehension	.47^*	.52^*	.03	.35^*	.61 (.47–.73)

	C1	C2	C3	C4	c²

Boston Naming	.60^*				.36 (.24–.47)
Word Recognition Latent Trait	.18^*	.13			.05 (.001–.17)
Decoding Latent Trait	.14	.22	.00		.07 (.00–.19)
Woodcock Passage Comprehension	.24^*	.24	.00	.00	.11 (.01–.24)

	E1	E2	E3	E4	e²

Boston Naming	.43^*				.19 (.16–.22)
Word Recognition Latent Trait	.06^*	.37^*			.14 (.12–.17)
Decoding Latent Trait	.03	.28^*	.27^*		.15 (.13–.18)
Woodcock Passage Comprehension	.07^*	.17^*	.04	.49^*	.27 (.24–.32)

Note. 95% confidence intervals in parentheses.

Significantly greater than zero. N (pairs) = 830.