A system for the diagnosis of specific language impairment in kindergarten children.

A valid and reliable diagnostic standard for language impairment is required for the conduct of epidemiologic research on specific language disorder. A rationale is provided for such a diagnostic system labeled the EpiSLI system. This system employed five composite scores representing norm-referenced performance in three domains of language (vocabulary, grammar, and narration) and two modalities (comprehension and production). Children who have two or more composite scores below-1.25 standard deviations were considered as children with language disorder. The performance of the EpiSLI diagnostic system was examined on a sample of 1,502 kindergarten children and it was shown that this diagnostic system yielded results that were consistent with clinician rating and previous research results.