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A comparison of two-coloured filter systems for treating visual reading difficulties
Roger Hall1, Nicola Ray, Priscilla Harries
1Mentoring Plus , Bath, Somerset, England , UK .
Disability and Rehabilitation
|May 1, 2013
Summary
Coloured filters effectively improve reading skills in children with visual stress. The Dyslexia Research Trust (DRT) filters showed greater improvements in spelling and non-word reading compared to the Harris filters.
Area of Science:
- Ophthalmology
- Developmental Psychology
- Educational Psychology
Background:
- Visual stress, characterized by reading difficulties, affects children's academic progress.
- Coloured filters in spectacles are a potential intervention for visual stress.
- Two main approaches exist: individually prescribed filters (Harris Foundation) and general blue/yellow filters (Dyslexia Research Trust).
Purpose of the Study:
- To compare the effectiveness of Harris Foundation and Dyslexia Research Trust (DRT) coloured filters in improving reading and spelling skills in children with delayed reading.
- To evaluate changes in irregular and non-word reading after 3 months of filter use.
Main Methods:
- A randomized, double-blind trial involving 73 children with delayed reading.
- Participants were assigned to wear either Harris or DRT filters for 3 months.
- Reading, spelling, and non-word reading skills were assessed before and after the intervention period.
Main Results:
- Both filter types significantly improved reading skills, with 40% of children showing a 6-month or greater improvement in reading age.
- The DRT filters led to significantly greater improvements in spelling ability and non-word reading compared to the Harris filters.
- Statistical significance was observed for reading improvement (p < 0.01), spelling (p = 0.05), and non-word reading (p < 0.05).
Conclusions:
- Coloured filters are an effective intervention for children experiencing visual stress and reading delays.
- The DRT filter system demonstrates superior efficacy in enhancing spelling and non-word reading skills.
- Rehabilitation and education professionals should consider coloured filters for children with visual reading difficulties.
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