Treatment effects on cluster development in the speech of 4-year-old children with speech disorder

Abstract

Purpose: This study examined the effectiveness of two differing interventions to improve the consonant cluster production in six children aged 4-5 years with concomitant speech sound disorder and expressive language difficulty. Method: Participants were selected for the study based on a high incidence of consonant clusters errors in their speech production. All participants had at least 75% of their cluster production attempts in error in their initial speech sample. The participants were randomly assigned to receive 24 hours of either a phonological awareness intervention with integrated speech targets (Gillon & Moriarty, 2005), or a morphosyntax intervention which alternated therapy sessions for language and speech targets (Haskill, Tyler, & Tolbert, 2001) Each intervention was administered in two blocks of 6 weeks separated by a 6-week therapy break. Hour-long small group intervention sessions were attended twice weekly by all participants. Consonant cluster productions were assessed using speech probes and standardised speech assessments. These were administered pre-intervention, postintervention, and at follow-up 3 months post-intervention. These measures were compared to identify any improvement in (a) word-initial cluster accuracy as a result of /s/ clusters being targeted in the phonological awareness intervention;(b) word-final cluster accuracy as a result of word-final morphemes being targeted in the morphosyntax intervention; and (c) cluster element accuracy as a result of improved production of the phonemes as singletons. Results: The data supported the hypotheses that targeting word-initial clusters in the phonological awareness intervention would lead to improvements in accuracy for target /s/ clusters, non-target /s/ clusters and singleton fricatives. Improvements in production of /s/ clusters, singleton fricatives, and untreated consonant + liquid