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mental retardation title

A new Program study shows that over 1/3 of California’s children with mental retardation are born with structural birth defects; in fact, a child with birth defects is almost 27 times more likely to have mental retardation at age 7. Even excluding those with Down syndrome and other chromosome disorders, children with birth defects have an 11 times higher risk of mental retardation.

Children with birth defects are at high risk to be severely affected: they account for 41.8% of those classified as having severe mental retardation compared to 29% of those in the mild category. A child with birth defects is less likely to have an associated developmental disorder—they comprise only 22% of the cases with cerebral palsy, epilepsy or autistic disorders.

Our study—looking at nearly 120,000 births in 8 Central Valley counties—includes only children followed by the California Department of Developmental Services; we did not ascertain children who died, had moved or who were receiving privately-funded services.

We found that 5/1000 school age children received state-funded services for mental retardation and related conditions. Overall

bullet 2.6/1000 had mild mental retardation (IQ score of 50-70)
bullet 2.4/1000 had severe mental retardation (IQ score of less than 50)
bullet 2.8/1000 had other developmental disabilities such as cerebral palsy, epilepsy or autistic disorders.
bullet 34.8% had one or more birth defects
bullet 18.2% had Down syndrome.

This study is undoubtedly an underestimate of the true incidence of mental retardation—as many as 1% of all school age children may be affected.

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