Effectiveness of intervention focused on vocational course vocabulary in post-16 students with (developmental) language disorder.

Abstract

People with language disorders (including developmental language disorder-DLD) often struggle to learn new words and, for young adults, this could affect their success in future work. Therefore, it is crucial to support their learning of career-specific vocabulary. However, little published evidence exists regarding the effectiveness of speech and language intervention for older adolescents and young adults with (developmental) language disorder (D)LD within a post-16 provision. To investigate whether for students with (D)LD in a post-16 environment, the addition of direct individual intervention from a speech and language therapist (SLT) teaching course-specific vocabulary leads to more progress than just in-course teaching on bespoke vocabulary measures. A total of 28 college-aged students (11 female and 17 male) with (D)LD (aged 16.0-19.9) participated in a within-participant study comparing progress with explicit vocabulary intervention plus in-course teaching versus in-course teaching alone. The participants were assessed at four time points (3 months pre-intervention, immediately pre- and post-intervention, 3.5 months after intervention) using bespoke vocabulary assessments with an equal number of nouns, verbs and adjectives. All participants received one-to-one vocabulary intervention from their usual SLT for 30 min per week for 9 weeks. The intervention had four main components: (1) to identify intervention focus, (2) to recap previously taught terms (using an online flashcard program), (3) to explicitly teach new words using word maps to help with: creating definition and pictorial representation, identification of word class and investigation of phonological and morphological properties, and (4) to add new words, with their definition and pictorial representation to online flashcard program. The results showed a stable baseline, then during the intervention term significant progress on words targeted only in lessons and significantly greater progress on words targeted both in lessons and SLT sessions. Progress was maintained for 14 weeks. Individuals with initially lower scores showed smaller intervention effects. In general, performance was higher on verbs and on the definition recognition task and lower on the production tasks, but all tasks improved with intervention. Direct one-to-one vocabulary intervention with an SLT can lead to significant gains in knowledge of course-specific terminology for college-aged students with (D)LD. The effectiveness of speech and language therapy services for this age group in a wider range of areas of language and social communication should also be investigated. What is already known on this subject Very few services exist for young adults with DLD, despite their persisting language difficulties and the detrimental impact of these on their academic attainment and employment prospects. Most careers involve specific vocabulary which is crucial to executing a role successfully and these need to be learned by those looking to move into these careers. However, children, adolescents and adults with DLD struggle to learn new words and may need help in this area. What this study adds to existing knowledge The young adults with (D)LD received 9 weeks of intervention targeting individualized course-specific vocabulary (nouns, verbs and adjectives), using word maps to focus on word forms, definitions, morphologically related words and syntactic information such as word class and how to use the word in a sentence. An online learning tool provided regular spaced retrieval practice of previously taught words and their definitions. The participants showed significant progress with learning course-specific vocabulary from attending lessons. However, they made significantly greater progress on those words which were also targeted in individual SLT sessions, regardless of word class. Progress was maintained over 14 weeks. What are the potential or actual clinical implications of this work? Direct one-to-one vocabulary intervention with an SLT can lead to significantly greater gains in the acquisition of targeted course-specific terminology for young adults with (D)LD than the vocabulary teaching available in lessons. Individual intervention delivered by SLTs should therefore be offered to this age group of students with (D)LD to maximize their ability to access the academic curriculum and their future careers. Indeed, the broader role of SLTs in helping these young adults to access the world of work and independent living should be further investigated and supported.