How do DLD and dyslexia affect reading and mathematics achievement?

Duff, D. M., Hendricks, A. E., Fitton, L., & Adlof, S. M. (2022). Reading and Math Achievement in Children With Dyslexia, Developmental Language Disorder, or Typical Development: Achievement Gaps Persist From Second Through Fourth Grades. Journal of Learning Disabilities, 1–21. https://doi.org/10.1177/00222194221105515


Aim of the paper:


There is little research on how Dyslexia and DLD affect reading and mathematics performance in schools. This study measured academic performance using school-administered tests from ages 6 to 9. This study aims to investigate whether there is bigger learning gap between typically developing children and those with dyslexia and/or DLD, as well as pointing out needed changes to the support systems for reading and language skills.


What was found:


  • School-administered tests revealed a similar growth rate for reading and math abilities for children with DLD and/or dyslexia and children with typical development from 2nd to 4th grade, however scores remained lower than average for children with DLD or dyslexia and the lowest for children with DLD and dyslexia.

  • Only 37% of children with DLD and/or dyslexia were receiving extra support. Also, children with dyslexia are twice as likely to receive extra support than children with DLD (33% of dyslexia only children received extra support and only 15% of DLD only children did), and more likely to receive extra help from a younger age.

  • From second to fourth grade, the gap between the skills of the children with dyslexia only and those with DLD only increased. Those with DLD only fell further behind those with dyslexia only. This may continue as they go through further years of education.

  • Other academic tests show that DLD and/or dyslexia can have functional academic impacts other than areas beyond reading and language comprehension skills.


What does this mean?


The school setting of this paper enabled an accurate evaluation of the effect of DLD on children in learning settings, which prior clinical studies have not been able to do. This study shows poorer progress as children with DLD develop in reading and mathematic skills. They also receive far less extra academic support in comparison to children with dyslexia. The results of this study call for increased action to improve academic support for children with language development difficulties, especially those with DLD as it is an underrepresented disorder.


Where can I read this paper?


This paper is open access, which means everyone can read it.

Please click here to find the full paper.