Speech Perception and Phonological Awareness Skills in Thai-speaking Children with Speech Sound Disorders

Introduction: Children with Speech Sound Disorders (SSD) may have difficulties with speech perception and/or phonological awareness. Research on this area remains limited in children who speak tonal languages, such as Thai. This study aims to investigate whether Thai-speaking preschool children with SSD show difficulties in speech perception and phonological awareness compared to age-matched typically developing (TD) children. The study also examines the relationships among age, speech production, vocabulary abilities, and speech perception and phonological awareness within both SSD and TD groups. Methods: A total of 76 Thai-speaking children (SSD n = 32, TD n = 44) in kindergarten levels 2-3, aged 4;0-6;6 years, participated in this study. All children completed speech and vocabulary assessments, as well as speech perception and phonological awareness experiments. The speech perception experiment included two tasks: 1) phonemic discrimination and 2) lexical and phonetic judgement. The phonological awareness experiment included three tasks: 1) initial phoneme identification, 2) rime awareness, and 3) lexical tone awareness. Results: Children with SSD did not perform differently from their TD peers when controlling for age and receptive vocabulary. Age predicted performance on phonemic discrimination and rime awareness in the SSD group, and on lexical and phonetic judgment and rime awareness in the TD group. Receptive vocabulary predicted only rime awareness in the SSD group. Speech production, as measured by percentage consonants correct, was not a significant predictor of performance in either group. Conclusion: The findings provide new evidence on speech perception and phonological awareness performance in Thai-speaking children. Children with SSD did not show difficulties in speech perception or phonological awareness in this study, which may be explained by the mild to moderate severity of SSD in these children. This study highlights the need to develop standardised Thai articulation and phonological assessments to facilitate more precise classification of children into specific SSD subtypes in future studies.