Measuring the economic impact of early intervention of speech impairment on educational outcomes and wellbeing: a study of the longitudinal study of Australian children

Objectives: The aim of this study is to investigate the impact of speech and language impairment (SLI) on educational outcomes and wellbeing in Australian children. Methods: A sample from the Longitudinal Study of Australian Children (LSAC) (N≈2340) was analysed using a random co-efficient model. The model examined the effects of speech impairment (measured by 4 measures: PPVT (Peabody Picture Vocabulary Test) assessment, parents expressive language concern and receptive language concern, speech therapy ) on 5 outcomes (literacy, maths reasoning, approach the learning, school adjustment and social-emotional wellbeing). Results: Results indicate that children with below average PPVT (direct assessment of receptive language impairment) had significantly lower maths and literacy scores in Year 2 and 3 (- 7.49% SE 0.00646), (-7.42% SE 0.0113) respectively. Children entering speech therapy at an older age had lower levels of school adjustment (-0.07 SE 0.0474) and parents receptive language concern was negatively associated with children’s self esteem at 6/7 and 8/9 yrs (social-emotional) (-8.34% SE 0.0130). Children with a positive approach to school (both across individuals and changes in an individual over time) had higher literacy, (14.8% SE 0.00485) numeracy (9.26 % SE 0.00916) , school adjustment (0.0316 SE 0.0159) and self esteem. (2.58% SE 0.00695). Lessons learned and implications: This study demonstrates there is a link between early interventions for SLI and improved outcomes in literacy and numeracy. Since there are clear links between school achievements and productivity gains the economic impact from early interventions for SLI could be significant. Further research is warranted.