Plain English Summary
Background and study aims
Up to half of all children with reading problems find it difficult to see text clearly; letters appear to blur, glare, go double or move around, and these problems can give them headaches. These visual symptoms probably result from reduced precision of timing visual events. There are good physiological reasons for supposing that viewing text through either simple blue or yellow coloured filters may improve the brain’s timing functions. We have found that we can predict which children are likely to benefit from blue or yellow or no filters. Using the appropriate filter for reading is often followed by rapid reading and spelling progress. However, there is no agreement about whether coloured filters can really help more than as a placebo. Clearly this question needs to be settled because if simple and cheap blue or yellow filters can really help reading difficulties, this low cost technique should be used wherever appropriate, in order to help a substantial proportion of the 10% of primary school children who have great difficulties learning to read. This study aims to assess the effects of blue and yellow coloured filters to see if it helps children with dyslexia learn to read.
Who can participate?
Children age 7 to 11 years with visual reading problems
What does the study involve?
Based on their visual symptoms, participants are allocated to a blue filter group or yellow filter group. Then, selected at random, the ‘blues’ are asked to wear either blue or placebo grey filters for 3 months, then all switch to blue. Likewise the ‘yellows’ are randomised to yellow or placebo grey, then all switch to yellow after 3 months. Participants use their filter when reading, and are followed up with reading history, psychometric (pen and paper tests) of their reading, spelling and general abilities together with the routine eye assessments at 3, 6 and 9 months.
What are the possible benefits and risks of participating?
The participants may benefit from improved reading from the appropriate colour filter more than by the placebo grey filter. None of the colours are likely to harm the children in any way.
Where is the study run from?
Dyslexia Research Trust Clinic (UK)
When is the study starting and how long is it expected to run for?
September 2014 to October 2022
Who is funding the study?
Dyslexia Research Trust (UK)
Who is the main contact?
Prof John Stein (Public)
CUREC - YB2015, Date and Version No: 06.08.15 version 1:2
The Effect of Yellow and Blue lenses on Reading and Spelling Skills
Children with visual reading problems will be helped to learn to read by viewing text through blue or yellow filters.
Oxford University Medical Sciences Div. Research Ethics Board, 01/09/2014, ref: MSD-IDREC-C -2014-024
Randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format yet, please use the contact details below to request a patient information sheet
Children's visual reading problems (dyslexia)
Based on their visual symptoms, participants are allocated to a blue filter group or yellow filter group. Then, selected at random, the ‘blues’ are asked to wear either blue or placebo grey filters for 3 months , then all switch to blue. Likewise the ‘yellows’ are randomised to yellow or placebo grey, then all switch to yellow after 3 months.
Participants use their filter when reading, and are followed up with psychometric and visual assessments at 3, 6 and 9 months.
Primary outcome measure
Single word reading progress is measured using BAS reading and spelling at baseline, 3, 6 and 9 months
Visual reading symptoms are measured using visual symptoms questionnaire at baseline, 3, 6 and 9 months
Secondary outcome measures
Optometric status is measured using standard optometric tests at baseline, 3 months, 6 months and 9 months
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Children with visual reading problems
2. Age 7-11
3. Male and female
Target number of participants
Participant exclusion criteria
1. English not first language
2. Any medical or neurological diagnosis
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Dyslexia Research Trust Clinic
179a Oxford Road
Dyslexia Research Trust
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Dyslexia Research Trust newsletter www.dyslexic.org.uk
Planned publication in educational and medical peer-reviewed journals.
Study protocol and additional documentation also available from Prof J Stein.
IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from Prof J Stein, Sherrington Building, Parks Road, OX1 3PT.
Intention to publish date
Participant level data
Available on request
Basic results (scientific)