Does viewing text through yellow or blue filters help dyslexic children to learn to read?
| ISRCTN | ISRCTN39964318 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN39964318 |
| Protocol serial number | CUREC - YB2015, Date and Version No: 06.08.15 version 1:2 |
| Sponsor | Dyslexia Research Trust |
| Funder | Dyslexia Research Trust |
- Submission date
- 02/02/2018
- Registration date
- 02/03/2018
- Last edited
- 13/11/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Signs and Symptoms
Plain English summary of protocol
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 using 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 2024
Who is funding the study?
Dyslexia Research Trust (UK)
Who is the main contact?
Prof John Stein (Public)
John.stein@dpag.ox.ac.uk
Contact information
Public
DPAG
Sherrington Building
Parks Road
Oxford
OX1 3PT
United Kingdom
 ORCID ID |
0000-0001-5843-8986 |
|---|---|
| Phone | +44(0) 1865 272552 |
| john.stein@dpag.ox.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Randomised controlled trial |
| Secondary study design | Randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | The Effect of Yellow and Blue lenses on Reading and Spelling Skills |
| Study acronym | BYLR |
| Study objectives | Current study hypothesis as of 24/02/2022: Can children with visual reading problems will be helped to learn to read by viewing text through blue or yellow filters? Previous study hypothesis: Children with visual reading problems will be helped to learn to read by viewing text through blue or yellow filters. |
| Ethics approval(s) | Oxford University Medical Sciences Div. Research Ethics Board, 01/09/2014, ref: MSD-IDREC-C -2014-024 |
| Health condition(s) or problem(s) studied | Children's visual reading problems (dyslexia) |
| Intervention | 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. |
| Intervention type | Device |
| Phase | Phase III |
| Drug / device / biological / vaccine name(s) | blue or yellow filters |
| Primary outcome measure(s) |
Single word reading progress is measured using BAS reading and spelling at baseline, 3, 6 and 9 months |
| Key secondary outcome measure(s) |
Optometric status is measured using standard optometric tests at baseline, 3 months, 6 months and 9 months |
| Completion date | 28/10/2024 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Child |
| Lower age limit | 7 Years |
| Upper age limit | 11 Years |
| Sex | All |
| Target sample size at registration | 200 |
| Total final enrolment | 68 |
| Key inclusion criteria | 1. Children with visual reading problems 2. Age 7-11 3. Male and female |
| Key exclusion criteria | Current key exclusion criteria as of 13/11/2025: 1. v. low intelligence 2. Any medical or neurological diagnosis _____ Previous key exclusion criteria: 1. English not first language 2. Any medical or neurological diagnosis |
| Date of first enrolment | 01/09/2016 |
| Date of final enrolment | 28/10/2024 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centre
Reading
RG1 7SN
England
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request, Stored in non-publicly available repository |
| IPD sharing plan | 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. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
13/11/2025: The following changes were made to the trial record:
1. The acronym was added.
2. The Phase was added.
3. The Drug/device/biological/vaccine name(s) was added.
4. The total final enrolment was added.
5. The key exclusion criteria were changed.
6. The study participating centres were updated.
24/02/2022: The following changes have been made:
1. The recruitment end date has been changed from 28/10/2022 to 28/10/2024.
2. The overall trial end date has been changed from 28/10/2022 to 28/10/2024 and the plain English summary has been updated to reflect this change.
3. The intention to publish date has been changed from 28/10/2023 to 28/10/2025.
4. The study hypothesis has been updated.
5. The statement "Stored in non-publicly available repository" has been added to the IPD sharing summary.
08/07/2020: The following changes were made to the trial record:
1. The recruitment end date was changed from 31/03/2019 to 28/10/2022.
2. The overall trial end date was changed from 31/08/2019 to 28/10/2022.
3. The intention to publish date was changed from 01/01/2020 to 28/10/2023.
