Measuring the economic impact of speech impairment on academic achievement and social wellbeing: a study of the longitudinal study of Australian children

The prevalence of speech and language impairment in 4-5 yr olds could be as high as 20%. Increasing evidence suggests that there are both short and long term effects of childhood speech impairment. The impact of speech impairment may include loss of potential in occupational and educational domains and reduced quality of life. The social and economic cost of communication impairment is significant to both individuals and society. High short- and medium-term costs are associated with children needing special education resources in school and repeating grades. High long-term costs to the individual (and society) are associated with children failing to finish school. To date there is little if any studies that have addressed the economic impact of speech impairment in Australian Children. The first stage of this study is to investigate the impact of speech impairment on educational outcomes and wellbeing. Three waves of the Longitudinal Study of Australian Children (LSAC) (Wave 1,2 and 3) (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 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). 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.