Condition category
Eye Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Amblyopia (also called lazy eye) is the most common disease affecting vision in childhood. Currently 30% of children treated for amblyopia do not reach normal vision after a year or more of treatment. Amblyopia is usually treated with glasses wearing and by patching the better eye (wearing an eye patch). There is controversy whether a long period of glasses wearing before patching, called refractive adaptation, helps in treating children with amblyopia. The aim of this study is to perform a trial to test whether refractive adaptation before patching improves the number of successfully treated children with amblyopia.

Who can participate?
Amblyopic children between 3 and 8 years of age

What does the study involve?
Participants are randomly allocated to one of two groups. One group wears glasses for 18 weeks before patching for amblyopia is started, whereas the other group wears the glasses for 3 weeks before patching.

What are the possible benefits and risks of participating?
The participants receive information material for parents, teachers and children about amblyopia. Decorated patches are given to the children. The waiting time for appointments is likely to be shorter. It could be that the total treatment time is reduced. Possible occurrence of side effects is very similar to the usual clinical treatment and could be rarely increase of squint, double vision or reduced vision in the better eye (which is almost always reversible).

Where is the study run from?
1. University of Leicester (UK)
2. Moorfields Eye Hospital (UK)
3. University of Graz (Austria)
4. University of Heidelberg (Germany)

When is the study starting and how long is it expected to run for?
June 2013 to August 2018

Who is funding the study?
Action Medical Research (UK)

Who is the main contact?
Prof. Irene Gottlob

Trial website

Contact information



Primary contact

Prof Irene Gottlob


Contact details

Professor Irene Gottlob (MD
Univ. Doz.
Professor of Ophthalmology
Ophthalmology Group
University of Leicester
Leicester Royal Infirmary
PO Box 65
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

The role of glasses wearing in amblyopia treatment: a randomised controlled multicentre trial



Study hypothesis

The number of children successfully treated after 720 hours of prescribed patching over 12 weeks is significantly higher following an initial period of 18 weeks glasses wearing period than 3 weeks glasses wearing period prior to patching therapy.

Ethics approval

Derby NRES Committee East Midlands, 28/03/2013, ref: 120878

Study design

Unmasked randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet




There are two study arms:
Refractive Adaptation Group (n=173): A period of 18 weeks glasses wearing (i.e. RA) will be followed by a period of 24 weeks combined patching (10hrs/day, 6 days/week) and glasses wearing.

Early Patching Group (n=173): A period of 3 weeks glasses wearing will be followed by a period of 24 weeks combined patching (10hrs/day, 6 days/week) and glasses wearing.

Participants will have an initial full ophthalmologist examination including cycloplegic refraction and will be examined subsequently at 6 weekly intervals with visual acuity measurements.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Number of children successfully treated after 720 hours of prescribed patching over 12 weeks following an initial period of either 3 weeks or 18 weeks glasses wearing prior to patching therapy

Secondary outcome measures

1. To compare the number of patients successfully resolved in ≤ 1080 hours of prescribed patching over 18 weeks, and in ≤ 1440 hours over 24 weeks. Where possible we will also compare the two groups in terms of final visual outcome, total duration of treatment and total amount of patching required
2. To estimate the levels of compliance to glasses and patch wearing
3. To explore the relationship between duration of glasses wearing and patching and improvement in vision
4. To explore whether anisometropes respond better to RA compared to strabismus/mixed patients.
5. To explore whether electronic monitoring influences compliance and visual outcomes
6. Ascertain opinions from carers and children about the study treatment study through a questionnaire given during and on completion of the study

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Children (aged 3 to 8 years) with newly detected amblyopia (difference of ≥ 0.3 LogMAR visual acuity between eyes)
2. A clinically significant refractive error (≥ 1.5D in at least 1 eye or 1D difference between the two eyes)
3. Able to perform the visual acuity test

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Children without amblyopia as defined above or with amblyopia as defined above but with other ophthalmic or neurological diseases, or premature children
2. Bilateral amblyopia (vision of better eye corrected visual acuity > 0.2 LogMAR) is also an exclusion criterion

Recruitment start date


Recruitment end date



Countries of recruitment

Austria, Germany, United Kingdom

Trial participating centre

Leicester Royal Infirmary
United Kingdom

Sponsor information


University of Leicester (UK)

Sponsor details

College of Medicine
Biological Sciences and Psychology
Level 4
United Kingdom

Sponsor type




Funder type


Funder name

Action Medical Research (UK)

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

Other non-profit organizations


United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

21/06/2017: The following changes were made to the trial record: 1. The recruitment end date was changed from 17/12/2015 to 29/09/2017. 2. The overall trial end date was changed from 17/06/2016 to 14/08/2018.