Prevalence of specific language impairment in 5 year-old children of an Iranian

Introduction: This Study estimated the prevalence of specific language impairment (SLI) in five-year old children. SLI is applied to children who exhibit a significant deficit in language ability yet display normal hearing, age-appropriate scores on tests of nonverbal intelligence, and no obvious signs of neurological damage. Materials and Methods: In this epidemiological study, 436 children at five years old, 221 boys and 215 girls were selected from all public and private preschool centers in the city of Semnan (Iran). The impairment was diagnosed during two phases. The focus of the phase one was the screening of children suspected to SLI by the relevant data gathered through a questionnaire specified for parents, in regard to motor, speech and language development adding family history of language or learning difficulties. In phase two, 19 Children who failed the screening and similar number of controls nominated for more investigating of some of their language properties by sampling of descriptive and conversational speech. The data obtained from the second phase provided a basis for diagnosis of SLI with 15 out of 19 suspected SLI children. Results: The findings provided an estimated overall prevalence rate of 3.44 percent. The prevalence estimate for boys was 3.61% and for girls 3.25%. Conclusion: The prevalence of SLI fell under some of the estimates in the studies of English speakers. However, it was within the identified range of DSM IV. Also, this condition was almost the same between the two sexes. These results might be a consequence of Persian language morphosyntactic features, the reliance on parents report for the screening, social characteristics of the region.