Behavior, language, and development in three-year-old children.

An epidemiological study of 3-year-old children showed there to be a marked association between behavior problems and language delay. Behavior problems were present in 14% of a random sample of 705 children, whereas 59% of 22 children with language delay had such problems. Data obtained from a battery of developmental tests were analyzed to examine the differences between children with behavior problems, matched controls, and children with language delay. It was found that children with behavior problems scored significantly lower on these tests, particularly those concerned with language. There were no significant differences in test scores between children with language delay only and those with combined behavior problems and language delay.