Non-word repetition in Persian learning toddlers with typical development

In the current research, non-word repetition (NWR) skills of Persian learning toddlers and its association with phonological accuracy and language measures, such as percentage consonant correct (PCC), mean length utterance (MLU), and expressive vocabulary was evaluated. First, the Persian task of NWR, comprising 15 non-words, was developed and validated. Forty-four typically developing Persian learning toddlers aged from 24 to 30 months were recruited in this project. Word and NWR responses were elicited during play. MLU was investigated using serial picture description. Furthermore, the Persian version of MacArthur-Bates communicative development inventories was completed by participants' parents. The association between NWR, word repetition, MLU, and vocabulary indices was measured. Excellent values were obtained for test-retest reliability, PCC of NWR (ICC = .94, 95% CI, .78-.94, p < .001) and PCC of word repetition (ICC = .96, 95%CI, .83-.96, p < .001). The values of PCC for NWR and PCC of word repetition were 80.32 +/- 13.44 and 83.51 +/- 9.91, respectively. The Wilcoxon ranked test showed that participants had better performance in word repetition than NWR (z = -.275, p = .02). Significant associations were found between NWR, word repetition, MLU, number of different words, number of total words, and the expressive vocabulary size. Sex, socioeconomic status, and age did not affect NWR in this study. The findings of the current research demonstrated that the Persian task of NWR is a valid and reliable test to measure the NWR and the scores of participants were substantially associated with phonological accuracy, MLU, and vocabulary measures.