Table 3.

Preliteracy skills at 6 years and school achievement at 9 years according to literacy outcome

	Familial risk
	Dyslexia		No-dyslexia		Control						Effect size (Cohen’s d)
Measure	M	SD	M	SD	M	SD	N	F	df	p	FRD vs. FRND	FRD vs. C	FRND vs. C
Preliteracy skills (6 years)
Rapid naming colours	0.58a	0.16	0.72b	0.18	0.75b	0.18	185	14.19	(2, 182)	<0.001	0.79	0.96	0.17
Phonological awareness
Blending	7.57a	5.70	11.56b	6.25	14.45c	5.14	189	19.51	(2, 186)	<0.001	0.78	1.34	0.56
Segmentation	5.08a	4.97	9.46b	6.67	12.32c	6.09	189	19.49	(2, 186)	<0.001	0.72	1.19	0.47
Letter knowledge
Receptive	13.61a	6.58	21.27b	6.59	22.73b	7.20	189	27.91	(2, 186)	<0.001	1.06	1.27	0.20
Productive	9.02a	6.28	17.66b	8.13	18.50b	8.22	188	24.89	(2, 185)	<0.001	1.05	1.15	0.10
School achievement (9 years)
Reading	28.64a	8.21	54.72b	12.10	61.53c	12.24	196	129.98	(2, 193)	<0.001	2.13	2.69	0.56
Arithmetic	−1.35a	1.61	0.15b	1.79	0.90c	1.75	196	24.22	(2, 193)	<0.001	0.86	1.29	0.43

F and df values refer to an ANOVA for the effect of group. Means in the same row that do not share subscripts differ at p < 0.05 on Tukey’s test. Cohen’s d is calculated using the SDs of the controls

FRD familial-risk dyslexia; FRND familial-risk no-dyslexia; C control