Objectives: It has been noted that stuttering is more prevalent in bilinguals than in monolinguals. The similarities of the languages involved have been mentioned to justify the difference between stuttering prevalence among bilingual and monolingual speakers. The aim of this study is to investigate the effect of language similarities on prevalence of stuttering among Kurdish-Farsi bilingual students.
Methods: In this cross-sectional descriptive analytic study, we examined all of Javanroud’s schools’ bilingual students. We used teacher referral method for the primary screening of speech disorders. Essential information about speech disorders, specifically stuttering, had been given to teachers before this primary step. The bilingual researcher then diagnosed stuttering students based on DSM-IV criteria through personal interview, text reading, and spontaneous speech in Kurdish and Farsi.
Results: Among 11425 bilingual students of Javanroud’s schools, 129 students were identified as stutterers. These findings indicated that overall prevalence of stuttering in this population is 1.13%. Among elementary, guidance and high school students the prevalence of stuttering was 2.06%, 0.87% and 0.5% respectively. Prevalence of stuttering among boys was 1.35% and 0.88% among girls. An overall male/female ratio was 1.5/1. Prevalence of stuttering in elementary, guidance and high school differed significantly (P=0.000). Prevalence of stuttering in males was significantly higher than females (P=0.034).
Discussion: Prevalence of stuttering among Javanroud’s bilingual students was higher than the universal accepted prevalence in monolinguals (1%) but lower than other studies in bilingual population. The similarities of Kurdish and Farsi languages play an important role in this and are discussed in the paper.