Profiles of vocal development in Korean children with and without cleft palate.

This study longitudinally investigated vocal development in Korean children from 9 to 18 months of age with and without cleft palate (CP). Utterance samples were collected from 24 children with and without CP at 9, 12, 15 and 18 months of age. Each utterance was categorised into levels of vocalisation using the Korean-translated version of the Stark Assessment of Early Vocal Development-Revised (SAEVD-R). The results showed children with CP produced a significantly higher rate of precanonical vocalisations (the combination of Levels 1, 2, and 3) and a lower rate of Level 4 and 5 vocalisations than children without CP. Both groups showed decreases in Levels 1 and 2 and increases in Level 5 from 9 to 18 months of age. A significant increase in the proportion of Level 4 vocalisations across age was observed only in children without CP. Young Korean children with CP showed lower proportions of advanced vocalisation levels characterised by canonical and complex syllable structures across 9 and 18 months of age compared to children without CP.