Room to read: The effect of extra-large letter spacing and coloured overlays on reading speed and accuracy in adolescents with dyslexia.
Bigger spaces between letters speed up reading and cut errors for dyslexic teens, while coloured overlays do nothing.
01Research in Context
What this study did
Researchers gave middle-schoolers with dyslexia two kinds of text. One had extra-wide spaces between letters. The other used coloured plastic sheets on top of the page.
They timed how fast each teen read and counted every word missed.
What they found
Wide letter spacing made the kids read faster and cut missed-word errors. The coloured overlays did nothing.
The change was simple: just hit the space bar a few more times between letters.
How this fits with other research
Schneider et al. (2006) found coloured overlays helped kids with autism read faster. The new study shows the same overlays do not help kids with dyslexia. Same tool, different diagnosis, different result.
Storey et al. (2020) and Storey et al. (2017) used computer phonics lessons to boost reading. Those studies taught new skills. The 2021 paper skips teaching and just changes how the text looks.
Alqahtani (2020) used iPad text-to-speech to make reading easier for young adults with intellectual disability. Both studies tweak the text, not the reader, and both saw gains.
Why it matters
If you work with dyslexic teens, try enlarging letter spacing before you buy coloured overlays or new software. It costs nothing, takes five minutes, and the study shows it works. Add two to three spaces between letters in worksheets, tests, or reading apps and measure the difference yourself next session.
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02At a glance
03Original abstract
BACKGROUND: Coloured overlay and extra-large letter spacing may improve reading speed and accuracy in individuals with dyslexia; however, research has yet to identify which types of reading errors are diminished. AIM: To determine the impact of extra-large letter spacing and colour overlay on reading and assess the impact of both interventions on reading errors. SAMPLE: Thirty-two dyslexic children were matched on age, verbal and non-verbal IQ with 27 children with no diagnosis of dyslexia. The average age of each group was 13 years. METHOD: Participants read four texts with either standard or extra-large letter spacing with or without a coloured overlay. RESULTS: Extra-large letter spacing significantly improved reading speed more substantially for the dyslexia group. In addition, extra-large letters significantly reduced the number of missed word errors made by the dyslexia group. In contrast, coloured overlays did not significantly impact reading speed or the reduction of errors. CONCLUSION: Increasing letter spacing is an effective way for teachers to improve reading skills in students with dyslexia.
Research in developmental disabilities, 2021 · doi:10.1016/j.ridd.2021.104065