Clinical and research congruence in identifying children with specific language impairment.

This paper reports on the results of a large multicenter project designed to develop an empirically based classification of preschool children with language impairments. A clinically selected population of 252 children with specific language impairments (SLI) was used to evaluate the reliability, coverage, and usefulness of both standard clinical and research definitions of such children. Varying degrees of congruence were found between the clinically identified children with SLI and those identified as SLI using discrepancy, deficit, and standardized operational criteria. Such mismatch between the original clinical identification and more standardized operational criteria may be related to different clinical perspectives, professional training, and limited assessment measures. These results suggest that there is a significant gulf between the clinical diagnosis of children with specific language impairment and more standardized operational criteria. It is suggested that the global concept of a "specific language impairment" may not be a useful concept for either clinical or research activities.