Family risk of dyslexia is continuous: individual differences in the precursors of reading skill.

The development of 56 children at family risk of dyslexia was followed from the age of 3 years, 9 months to 8 years. In the high-risk group, 66% had reading disabilities at age 8 years compared with 13% in a control group from similar, middle-class backgrounds. However, the family risk of dyslexia was continuous, and high-risk children who did not fulfil criteria for reading impairment at 8 years performed as poorly at age 6 as did high-risk impaired children on tests of grapheme-phoneme knowledge. The findings are interpreted within an interactive model of reading development in which problems in establishing a phonological pathway in dyslexic families may be compensated early by children who have strong language skills.