Effects of Recast Length on MLU Development in Children with Developmental Language Disorder

Abstract

Even when a treatment is known to be effective, details around how the treatment is delivered can enhance or lessen its effectiveness. In this study, we employed a well-established treatment, Enhanced Conversational Recast therapy, and manipulated the length of the clinician recasts provided to children. Preschool children with developmental language disorder either heard recasts that were four or fewer words or five or more words in length during treatment of a single grammatical form. For this master’s thesis, we examined the effect of recast length on the development of children’s utterance length pre- to post-treatment, hypothesizing that children who heard longer recasts would show a greater change in MLU in comparison to children who heard short recasts. Overall, we found no difference in MLU growth associated with recast length, suggesting that presenting longer linguistic models does not necessarily benefit MLU development in early childhood.