Document Type : Original Articles


1 Department of Speech Therapy, Rehabilitation School, Shiraz University of Medical Sciences, Shiraz, Iran

2 Urmia Universiry of Medical Sciences, Urmia, Iran


Background: Specific Language Impairment (SLI) is one of the most common developmental problems resulting in referral to speech therapy clinics in the preschool years. A number of studies have been conducted to determine the prevalence of SLI in different populations. However, the prevalence of childhood language disorders in Iranian population is unknown because of the limited epidemiologic studies in the field. The aim of this study was therefore, to estimate the prevalence of SLI in 5-year-old Persian-speaking children. Methods: This research was an epidemiological study which conducted in a three-month period in the spring of 2015 in Shiraz. The sample size was 180 children aged 5 years old including 95 boys and 85 girls whom recruited from 12 preschool centers of 9 urban areas in Shiraz by stratified sampling. The EpiSLI system was used to diagnose SLI. The Persian version of Test of language Development (TOLD-P: 3) was employed to evaluate the children’s oral language skills. A number of descriptive statistics were calculated. In addition, Chi-square test was used to analyze the correlation between the prevalence of SLI with sex and area. The significant level was set to 0.05.Results: The estimated prevalence of SLI in the population under study was estimated to be %3.3. In addition, the estimated prevalence of SLI in boys and girls was 4.2% and 2.4%, respectively. There were no significant correlation between the estimated prevalence of SLI with sex and area (P > 0.05). Conclusions: According to the findings of this study, it is important to employ screening system to find preschool children with SLI to prevent subsequent problems.


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