Cantonese Oral and Speech Motor Assessment for Preschool Children With and Without Speech Sound Disorders.

Purpose: Oral and speech motor abilities are key components of assessments of Cantonese speakers with speech sound disorder (SSD), especially childhood apraxia of speech (CAS). This study aims to investigate the oral and speech motor abilities of Cantonese preschool children with and without SSD using an adapted version of a popular English assessment protocol.

Method: A total of 104 Cantonese-speaking children, aged between 3 and 5 years, were assigned to three main groups: typical development (TD), non-CAS SSD, and CAS. They were tested using the Cantonese Oral and Speech Motor Assessment (COSMA), an adapted version of the Robbins and Klee protocol. Sixteen perceptual and acoustic measures were employed to evaluate oral and speech motor abilities in the children, and binary logistic regression models were constructed to assess the predictive values of these measures for broad SSD diagnosis, combining the CAS and non-CAS SSD groups.

Results: Statistically significant differences were observed among the TD, non-CAS SSD, and CAS groups on seven COSMA measures, including measures of oral structures, speech and nonspeech oral functions, and speech motor abilities. Age progression was found on five measures. Total structural score and multisyllabic word accuracy emerged as significant predictors of broad SSD diagnosis.

Conclusions: This study supports the preliminary success of the COSMA in differentiating Cantonese preschool children with and without broad SSD. The TD group's performance offers a reference for local clinical use. Future research should include diverse groups of children with various SSD types to enhance understanding of oral and speech motor skills among Cantonese speakers and related clinical issues.

Supplemental material: https://doi.org/10.23641/asha.30162007.