Speech Sound Performance in Preschool Children with and without Cluttering: A Comparative Analysis of Phonological and Articulatory Abilities

This study investigates differences in speech sound performance, specifically phonological and articulatory abilities, between preschool children with and without cluttering. Phonological ability was assessed using a nonword repetition task and the Articulatory and Phonological Test for Mandarin-Speaking Children (APTMC), which includes a minimal-pair test and phonological processing analysis through sentence and picture subtests. Articulatory ability was evaluated through diadochokinetic (DDK) tasks, as well as measures of syllable and initial consonant accuracy from the APTMC sentence and picture subtests.

Children were categorized into the cluttering group (GWC, n = 30) and the non-cluttering group (GWNC, n = 30) based on the speech rate subscale of Cluttering Severity Instrument–Mandarin Edition (CSI-M), and the reports from parents and teachers. A score of ≥24, combined with teacher and parent reports of rapid, unintelligible speech, indicated cluttering, while children scoring <24 and exhibiting no speech-language disorders were assigned to the GWNC group. Participants were matched for age (5–7 years), gender, and socioeconomic status.

Speech samples were transcribed verbatim to identify disfluency types and phonological processes. Subtest scores from the APTMC, nonword repetition syllable accuracy, and DDK completion rates were analyzed using independent samples t-tests and two-way repeated measures ANOVA to compare group performance. Key Findings:

Phonological Ability: Children with cluttering (GWC) exhibited significantly higher error rates in the minimal-pair test and lower accuracy in high- and low-frequency three- and four-syllable nonword repetition tasks compared to their non-cluttering peers. They also demonstrated a higher occurrence of phonological processes, particularly stopping, backing, affrication, deaspiration, and assimilation.
Articulatory Ability: GWC showed significantly lower syllable accuracy, as well as reduced initial consonant accuracy in both the sentence and picture subtests of the APTMC. However, no significant differences were found between groups in DDK task performance.
These findings indicate that preschool children with cluttering exhibit substantial deficits in phonological and articulatory skills compared to their non-cluttering counterparts, except in relatively simple motor-based DDK tasks. Study limitations and future research directions are discussed.