A Systematic Review of Interventions for Late Talkers: Intervention Approaches, Elements, and Vocabulary Outcomes.

PURPOSE: The aim of this systematic review was to examine the empirical evidence on interventions for late talkers between 18 and 42 months according to type of intervention approach (direct, indirect, and hybrid), reporting of intervention elements, and outcomes for receptive and expressive vocabulary. METHOD: This review was registered with PROSPERO and followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Eleven databases were systematically searched with 34 intervention studies involving 1,207 participants meeting criteria. Studies were categorized as using a direct, indirect, or hybrid intervention approach, then examined according to intervention elements, vocabulary outcomes, as well as reported tools and type of score used to evaluate outcomes. RESULTS: Across 34 studies, nine used a direct intervention approach, 10 an indirect intervention approach, and 14 a hybrid intervention approach. One study compared direct and hybrid intervention approaches. All indirect and hybrid approaches included parent training; direct approaches did not. The type and degree of reporting of other intervention elements, as well as the tools and type of score used to evaluate outcomes, varied within and across approaches. Overall, improvements in expressive vocabulary were reported by 93% of studies, with variable results for the nine studies reporting receptive vocabulary outcomes. CONCLUSIONS: The direct, indirect, and hybrid intervention approaches were typified by specific intervention elements; however, there was diversity in how other elements comprising the approaches were arranged. When making decisions about which intervention approach to use, clinicians need to be mindful of the differences among approaches, how they discuss those differences with parents, and which approaches and elements might be best suited to individual children and their families. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21291405.

Vocabulary Acquisition and Usage for Late Talkers Treatment: Effect on Expressive Vocabulary and Phonology.

Purpose This study examined the effect of Vocabulary Acquisition and Usage for Late Talkers (VAULT) treatment on toddlers' expressive vocabulary and phonology. Parent acceptability of VAULT treatment was also considered. Method We used a nonconcurrent multiple baseline single case experimental design with three late talking toddlers aged 21-25 months. The treatment was delivered twice weekly in 30-min sessions for 8 weeks by a rotating team of four speech-language pathologists. Toddlers heard three of their 10 strategically selected target words a minimum of 64 times in play activities each session. Expressive vocabulary and phonology was assessed pre-post, with parent interviews conducted posttreatment. Results All toddlers increased production of target words and expressive vocabulary. Ambient expressive vocabulary size increased by an average of 16 words per week (range of 73-169 words learned over the treatment period). On a 20-item, single-word speech assessment, the toddlers' phonetic inventories increased on average from three to seven consonants, and five to eight vowels. Two toddlers used protowords pretreatment, which were replaced by recognizable attempts at words posttreatment. Parents reported the treatment was acceptable for the child and their family with future consideration of parent-based delivery of the treatment in the home. Conclusions The results of this treatment provide further evidence of a model of intervention informed by the principles of implicit learning, and the interconnectedness of phonological and lexical learning. Investigation is required to establish the efficacy and feasibility of VAULT in clinical contexts. Supplemental Material https://doi.org/10.23641/asha.14714733.