Lexical diversity in Persian late talkers: A pilot study

The first diagnostic feature of late- children talkers is the low number of descriptive vocabulary coffers compared to peers. The purpose of this study was to compare the lexical variation (TTR) between late and spoken Persian language children in the age range of 2-3 years. In this pilot cross-sectional-comparative study, 8 late talkers and 8 normal children matched according age, gender and education of mother, were participated. These children did not have any neurological and motor deficit, hearing impairment, autism, and intellectual disabilities. So, report of mothers was used for determination of words in expressive vocabulary of both groups. Words were parted to 4 classes of nouns, verbs, modifier words and grammatical words. Mean of TTR in 4 classes was compared in both groups using Mann Whitney U test. Results indicated that the mean frequency of noun class to the total words in late talkers is significantly more than typical children. The mean frequencies of verb and modifier classes to the total words in typical children are significantly more than late talkers. The mean frequency of grammatical words class to the total words in late talkers is more than typical children but this difference isn’t significant (P<0.05). Increasing of TTR in late talker’s noun category indicated a delay in development of expressive vocabulary. Reasons, prognosis and need of preventive intervention have been discussed.