Efficacy of Response Cost Treatment in Preschool Children Who Stutter

Abstract

Early intervention in children who stutter (CWS) warrants relatively better treatment outcomes when compared to adults who stutter (AWS). However, unlike AWS evidence base regarding treatment efficacy in preschool CWS is limited. Further, this limited group of studies has focused only on specific intervention programs. Majority of the literature on efficacy studies in CWS have used the Lidcombe program, Westmead program, RESTART-DCM, or Parent-child interaction as intervention approaches. Besides, the existing evidence is majorly the findings from western context. It is observed that there is a dearth of literature on treatment efficacy studies in the Indian context, particularly for preschool CWS. Further, a direct implementation of the aforementioned intervention programs may not be feasible in the Indian context. Thus, this study aimed to assess the efficacy of a potential treatment approach, i.e., Response Cost (RC) treatment in preschool CWS. Twenty-seven Kannada-speaking preschool CWS were provided treatment for stuttering using a structured RC treatment program. Detailed baseline assessment was carried out for all the participants followed by the establishment phase of intervention which involved four levels – sentence, continuous speech, narration, and conversation. Participants were discharged from treatment program once they achieved 95% fluency or more. After discharge, participants were followed up at 1-month, 3-month, and 6-month to assess the maintenance of fluency skills. Spontaneous speech samples in both within-clinic and beyond-clinic conditions were recorded at each of the time points. The recorded speech samples were further analyzed for the following outcome variables: percentage of syllables stuttered (%SS), clinician and parent severity ratings (CSR & PSR), speech naturalness ratings, and speech rate (overall rate and articulation 2 rate). Further, parent perception of stuttering was also assessed pre- and post-treatment using Palin Parent Rating Scales (PPRS). Results of the study revealed a significant reduction in %SS and severity rating post-treatment, indicating a reduction in disfluencies. Speech naturalness ratings were observed to have improved post-treatment. Further, the overall rate of speech (syllables per minute) increased post-treatment, reflecting the reduction in disfluencies. In contrast, no significant difference was found in articulation rate (syllables per second) post-treatment, which implies no change in speech production characteristics of the participants. Results of PPRS indicated that parents perceived a significant reduction in the impact of stuttering on children and a significant increase in their knowledge and confidence in managing stuttering. Furthermore, no significant changes were seen for the majority of the outcome variables on three follow-up assessments which indicated that the fluency skills achieved using RC treatment were maintained up to 6-months of discharge. Overall, RC treatment shows potential as an intervention program for preschool CWS. The implications, limitations and future directions are also discussed in detail.