Effects of multidomain risk accumulation on cognitive, academic, and behavioural outcomes.

This longitudinal study examined the predictive associations between cumulative multidomain risk factors and cognitive (IQ), academic (reading fluency), and social adaptive outcomes at 8 to 9 years among 190 children with or without familial risk for dyslexia. Other risk factors included parental and neurocognitive risks assessed when the children were 1 to 6 years of age. Risks accumulated more among children with familial risk for dyslexia than among children without familial risk. A higher number of risks was associated with poorer performance in all outcome measures as postulated by the cumulative risk model. However, when the effects of individual risk variables were controlled for at the outset, the cumulative risk indices did not have incremental effects beyond those of individual risks. This suggests that the detrimental effect of several risks was due to the content-specific effect of individual risks. Children with familial risk were not differentially affected by the number of risks.