Refractive ErrorsSWISHNCT04077086
Correcting Myopia Among Secondary School Children to Increase Academic High School Attendance Rates in Rural Communities
A study testing Spectacles in people with Refractive Errors, run by Queen's University, Belfast at 3 sites in 2 countries.
Trial summary
Chinese children are some of the most short-sighted in the world, but only one in five children in poor areas who needs glasses has them. Our team has already shown in other trials that giving children free glasses leads to better grades and that free glasses have a bigger impact on grades than factors like parents'… Read more about this study
- Who is it for?
- Ages Up to 18 years
- Conditions the study is for
- Refractive Errors
- What is being tested?
- Spectacles
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10,000 participants
- Where
- 3 sitesin 2 countries
- Study dates
- 28 Nov 2024to 30 Aug 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Up to 18 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- Year 1 classes (likely age 12-15 years) at the recruited schools
- Those who will be in the second year of middle school when the intervention begins the next year
- Have uncorrected (without glasses/presenting) visual acuity of ≤6/12 in both eyes
- Refractive error meets cut-offs shown to be associated with significantly greater improvement in visual acuity when corrected (myopia ≤-0.75 diopters (D, or astigmatism (non-spherical refractive error) ≥1.00 D)
- Visual acuity can be improved to >= 6/7.5 in at least one eye with glasses.
Who cannot join
- Hyperopia ≥ 2.00 D
- Presence of visually-significant ocular condition besides refractive error
Trial locations and contacts
3 sites in 2 countries.
3 sites in 2 countries
China2 sites
He Eye Specialist Hospital
Shenyang, Liaoning, 110163
Ningxia University
Yinchuan, Xixia, 750021
United Kingdom1 site
Centre for Public Health
Belfast, Northern Ireland, BT12 6BJ
About this study
Official title: SWISH (See Well to Stay In ScHool): Randomised Trial of Spectacle Distribution to Secondary School Children With Myopia to Increase Academic High School Attendance Rates in Rural Communities)
Chinese children are some of the most short-sighted in the world, but only one in five children in poor areas who needs glasses has them. Our team has already shown in other trials that giving children free glasses leads to better grades and that free glasses have a bigger impact on grades than factors like parents' education level and the amount of money a family has. The effect on grades from glasses is greater than from other health services in school, like giving vitamins. Only about one in three children in rural China goes on to a regular, non-vocational high school. The investigators would like to show the Chinese government strong evidence of what glasses can do to help children continue their education, in order to help convince the government to carry out national programs to provide free glasses for children who need them.
Study Plan: The investigators will choose 111 middle schools at random in Liaoning, northern China, and all children in Year 1 at each school will go at random into one of two groups: either a group getting free glasses, with support from teachers to push them to wear the glasses ("Intervention") or a group getting just glasses prescriptions ("Control.") The main study outcome will be the proportion of children going on to academic (as opposed to vocational) high school, and the study is powered to detect a 10% difference in this figure between groups.The study will also assess whether children wear their glasses at school and how often they use blackboards (which disadvantage short-sighted children) vs textbooks to learn from. These other outcomes will help us to better understand the causal pathway between vision and high school attendance. We will also study the total cost of providing glasses and the teacher support to wear them per additional student attending academic high school, as well as student mental health outcomes. We will also collect data on the progression of nearsightedness. The hypothesis of this study is that providing glasses will increase academic high school attendance.
Read the detailed description
Research question: Will providing free glasses to myopic rural Chinese students, with a teacher incentive to promote use, increase academic high school attendance?
Design: Cluster-randomised controlled trial
Rationale: Rural Chinese children have high myopia prevalence, but poor access to glasses. Our previous trials show giving free glasses significantly improves academic performance, with greater effect size than parental education or family income, equaling or exceeding other classroom-based medical interventions. Non-vocational (academic) high school attendance is only 30% in rural western China. Strong evidence of educational benefit from glasses is needed to spur adoption of national distribution programs.
Methods: Children in Year 1 at 111 randomly-selected middle schools in Liaoning, Northern China, will be randomized by school to receive free glasses and a trial-proven teacher-based incentive to promote wear (Intervention) or prescriptions only (Control). The main outcome 3 years later will be high school attendance (powered to detect 10% difference between study groups); secondary outcomes of compliance and use of near versus distance classroom learning aids will elucidate biological plausibility of a causal pathway between myopia correction and learning. Local knowledge and attitudes about myopia and spectacle use and intervention cost-effectiveness will be studied.
Statistical methods to be employed in the analysis and justification for the choice of sample size:
Adjusted- and unadjusted-comparison of the difference between study groups
Principal analyses for the main trial will include:
- Of attendance at academic high school after Year 3 of middle school (as opposed to following a vocational pathway or leaving school).
- of observed spectacle wear at un-announced examinations at school and for self-efficacy scores.
- of mental health outcomes after Year 1 year of intervention
Sample size: Assuming 120 students per school undergoing vision screening, 50% of children failing vision screening, 30% of these needing glasses, α=0.05, intra-class correlation=0.10, explained variation by covariates=0.40, difference between the groups in the main study outcome=10%, high-school attendance rate in the Control group=50%, a sample size of 111 middle-schools (55 or 56 in each group) will provide power=80%.
Loss to follow-up in our previous school-based trials in China, SWLW I and II, was approximately 4% over the course of one school year, and so our calculations here assume a loss to follow-up of 10% over 2-3 years. However, we have not adjusted for non-compliance because we will use a strict intention-to-treat analytic approach where children in schools allocated to the Intervention group will be analysed as such irrespective of compliance and because our intention is to test the policy of making free glasses available to those students who need them, rather than the effect of those students actually wearing the glasses. Further, our expected effect size is based conservatively on previous trials with compliance rates of approximately 40%, which we feel can be improved on in the current trial with teacher incentives as above.
- Conditions
- Refractive Errors
- Being tested
- Spectacles
- Keywords
- Refractive error, Myopia, Academic high school attendance, Education attainment, Spectacle wear compliance, Mental health well-being, Progression of shortsightedness
- Medical subject headings
- Refractive Errors, Myopia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SpectaclesDevice
Also called Glasses
Intervention group children in middle school Year 1 will receive spectacles in December 2024. Assuming that the relevant effects of treatment (glasses wear) on the main study outcome are complete once examinations determining high school attendance are finished at the end of Middle School Year 3, Intervention participants will have undergone 32 months (December 2024 - July 2027) of treatment by the endpoint of the trial.
| Study group | Role | What they receive |
|---|---|---|
| Intervention | Experimental | Children at Intervention schools will receive free spectacles of a design they select, based on the child's measured refractive power and dispensed at school by the study optometrist. Additionally, teachers (but not children) in eligible classes will be informed that if 80% spectacle compliance as measured across three separate unannounced inspections was achieved, they will be given an incentive of an conditional cash transfer. The cash transfer will be deposited into the teacher's bank accounts directly. Receives: Device: Spectacles |
| Control | No intervention | Children at Control schools will receive a glasses prescription and letter to the parents informing them of the refractive status of their child, with free glasses provided only at the end of the trial. No teacher incentive will be offered. Service offered to the Control group exceeds standard care, in that no school-based programs of vision screening and refraction currently exist in the study area, or in most of rural China. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Academic high school attendance
Proportion of children who continue to academic high school as opposed to vocational high school or no additional schooling, assessed by systematically contacting parents, teachers and students to ascertain enrolment status
Measured: In July following completion of Year 3 of Middle School. This occurs after 32 months of participant followup.
Secondary outcomes (8)
Compliance with spectacle wear
Actual presence of spectacles on the child's face (rather than having glasses at school) at the time of an unannounced examination.
Measured: After 12 months of participant followup
Blackboard use
Frequency of blackboard versus textbook use on a questionnaire administered to class teachers, and answered as "all", "most", "about half", little" or "none" of teaching.
Measured: After 12 months of participant followup
Cost effectiveness of intervention.
Calculated as ratio of incremental cost to proportion of children who continue to academic high school as opposed to vocational high school or no schooling. Incremental cost is the difference of costs between implementation of intervention and control. Intervention costs will comprise the screening test, glasses (including replacements) and teacher incentives.
Measured: At study closeout, after 32 months of participant followup
Depression and Anxiety
Depression and anxiety score measured with Anxiety Stress Scale (DASS). The score range for depression, anxiety and stress are 0-42, with higher score indicates more severe mental health problems.
Measured: At baseline and 12 months post-treatment
Self Esteem
Self-esteem score measured with the Rosenberg Self-esteem Scale. The scores range from 0-30, with higher scores indicate higher self-esteem.
Measured: At baseline and 12 months post-treatment
Emotional and behavioral problems
Emotional and behavioral problems score using the Strengths and Difficulties Questionnaire (SDQ), with difficulties score ranges from 0 to 40, Prosocial scale ranges from 0-10, with higher score indicates severe mental health and behavioral problems.
Measured: At baseline and 12 months post-treatment
Progression of Shortsightedness
Progression of Shortsightedness will be measured using change in refraction over time
Measured: At baseline and 12 months post-treatment
Parents' and students' attitude towards spectacle wear
The primary data collection instruments are two tailored, semi-structured interview guides: one designed for the parents/guardians, and one developmentally adapted for the students. Rather than utilizing rigid survey questions, these qualitative instruments are comprised of open-ended prompts, scenarios.
The students interview guide has been specifically adapted for 7th-grade students (aged 12-13). It utilizes age-appropriate terminology and focuses heavily on adolescent-specific barriers, such as peer pressure, cosmetic concerns, and school dynamics.
Measured: After baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Sep 2019
- Study start28 Nov 2024
- Primary completion30 Aug 2027 (estimated)
- Study completion30 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Refractive ErrorsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Children in Year 1 at 111 randomly-selected middle-schools in Liaoning, northern China, will be randomized by school to receive free glasses and a teacher-based incentive to promote wear, or prescriptions only.
- Masking
- Double blind
- Who is masked
- Investigator, Outcomes assessor
- Enrolment
- 10,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Queen's University, Belfast
- Sponsor type
- University, hospital or other
- Collaborators
- Zhongshan Ophthalmic Center, Sun Yat-sen University, Stanford University, New England College of Optometry, Clearly, Ningxia Medical University, He Eye Hospital, He University
- Responsible party
- Principal investigator, Nathan Congdon, Queen's University, Belfast
- Investigators
- Nathan Congdon, MD, MPH, Principal investigator, Queen's University, Belfast
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04077086
- Sponsor's protocol ID
- MR/S023208/1
- Acronym
- SWISH
- Status last verified
- Sep 2026
- First submitted
- 7 Aug 2019
- Last updated
- 8 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- SWISH (See Well to Stay In ScHool): Randomised Trial of Spectacle Distribution to Secondary School Children With Myopia to Increase Academic High School Attendance Rates in Rural Communities)
- ClinicalTrials.gov ID
- NCT04077086
- Acronym / sponsor ID
- SWISH / MR/S023208/1
- Conditions
- Refractive Errors
- Keywords
- Refractive error, Myopia, Academic high school attendance, Education attainment, Spectacle wear compliance, Mental health well-being, Progression of shortsightedness
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 10,000 participants (estimated)
- Lead sponsor
- Queen's University, BelfastUniversity, hospital or other
- Collaborators
- Zhongshan Ophthalmic Center, Sun Yat-sen University, Stanford University, New England College of Optometry, Clearly, Ningxia Medical University, He Eye Hospital, He University
- Study start
- 28 Nov 2024 (actual)
- Primary completion
- 30 Aug 2027 (estimated)
- Study completion
- 30 Aug 2027 (estimated)
- First posted
- 4 Sep 2019 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Chinese children are some of the most short-sighted in the world, but only one in five children in poor areas who needs glasses has them. Our team has already shown in other trials that giving children free glasses leads to better grades and that free glasses have a bigger impact on grades than factors like parents' education level and the amount of money a family has. The effect on grades from glasses is greater than from other health services in school, like giving vitamins. Only about one in three children in rural China goes on to a regular, non-vocational high school. The investigators would like to show the Chinese government strong evidence of what glasses can do to help children continue their education, in order to help convince the government to carry out national programs to provide free glasses for children who need them.
Study Plan: The investigators will choose 111 middle schools at random in Liaoning, northern China, and all children in Year 1 at each school will go at random into one of two groups: either a group getting free glasses, with support from teachers to push them to wear the glasses ("Intervention") or a group getting just glasses prescriptions ("Control.") The main study outcome will be the proportion of children going on to academic (as opposed to vocational) high school, and the study is powered to detect a 10% difference in this figure between groups.The study will also assess whether children wear their glasses at school and how often they use blackboards (which disadvantage short-sighted children) vs textbooks to learn from. These other outcomes will help us to better understand the causal pathway between vision and high school attendance. We will also study the total cost of providing glasses and the teacher support to wear them per additional student attending academic high school, as well as student mental health outcomes. We will also collect data on the progression of nearsightedness. The hypothesis of this study is that providing glasses will increase academic high school attendance.
Detailed description
Research question: Will providing free glasses to myopic rural Chinese students, with a teacher incentive to promote use, increase academic high school attendance?
Design: Cluster-randomised controlled trial
Rationale: Rural Chinese children have high myopia prevalence, but poor access to glasses. Our previous trials show giving free glasses significantly improves academic performance, with greater effect size than parental education or family income, equaling or exceeding other classroom-based medical interventions. Non-vocational (academic) high school attendance is only 30% in rural western China. Strong evidence of educational benefit from glasses is needed to spur adoption of national distribution programs.
Methods: Children in Year 1 at 111 randomly-selected middle schools in Liaoning, Northern China, will be randomized by school to receive free glasses and a trial-proven teacher-based incentive to promote wear (Intervention) or prescriptions only (Control). The main outcome 3 years later will be high school attendance (powered to detect 10% difference between study groups); secondary outcomes of compliance and use of near versus distance classroom learning aids will elucidate biological plausibility of a causal pathway between myopia correction and learning. Local knowledge and attitudes about myopia and spectacle use and intervention cost-effectiveness will be studied.
Statistical methods to be employed in the analysis and justification for the choice of sample size:
Adjusted- and unadjusted-comparison of the difference between study groups
Principal analyses for the main trial will include:
- Of attendance at academic high school after Year 3 of middle school (as opposed to following a vocational pathway or leaving school).
- of observed spectacle wear at un-announced examinations at school and for self-efficacy scores.
- of mental health outcomes after Year 1 year of intervention
Sample size: Assuming 120 students per school undergoing vision screening, 50% of children failing vision screening, 30% of these needing glasses, α=0.05, intra-class correlation=0.10, explained variation by covariates=0.40, difference between the groups in the main study outcome=10%, high-school attendance rate in the Control group=50%, a sample size of 111 middle-schools (55 or 56 in each group) will provide power=80%.
Loss to follow-up in our previous school-based trials in China, SWLW I and II, was approximately 4% over the course of one school year, and so our calculations here assume a loss to follow-up of 10% over 2-3 years. However, we have not adjusted for non-compliance because we will use a strict intention-to-treat analytic approach where children in schools allocated to the Intervention group will be analysed as such irrespective of compliance and because our intention is to test the policy of making free glasses available to those students who need them, rather than the effect of those students actually wearing the glasses. Further, our expected effect size is based conservatively on previous trials with compliance rates of approximately 40%, which we feel can be improved on in the current trial with teacher incentives as above.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Children in Year 1 at 111 randomly-selected middle-schools in Liaoning, northern China, will be randomized by school to receive free glasses and a teacher-based incentive to promote wear, or prescriptions only.
| Arm | Type | Receives |
|---|---|---|
| Intervention | Experimental | Device: SpectaclesChildren at Intervention schools will receive free spectacles of a design they select, based on the child's measured refractive power and dispensed at school by the study optometrist. Additionally, teachers (but not children) in eligible classes will be informed that if 80% spectacle compliance as measured across three separate unannounced inspections was achieved, they will be given an incentive of an conditional cash transfer. The cash transfer will be deposited into the teacher's bank accounts directly. |
| Control | No intervention | –Children at Control schools will receive a glasses prescription and letter to the parents informing them of the refractive status of their child, with free glasses provided only at the end of the trial. No teacher incentive will be offered. Service offered to the Control group exceeds standard care, in that no school-based programs of vision screening and refraction currently exist in the study area, or in most of rural China. |
Who may qualify
- Ages
- Up to 18 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (5 listed)
- Year 1 classes (likely age 12-15 years) at the recruited schools
- Those who will be in the second year of middle school when the intervention begins the next year
- Have uncorrected (without glasses/presenting) visual acuity of ≤6/12 in both eyes
- Refractive error meets cut-offs shown to be associated with significantly greater improvement in visual acuity when corrected (myopia ≤-0.75 diopters (D, or astigmatism (non-spherical refractive error) ≥1.00 D)
- Visual acuity can be improved to >= 6/7.5 in at least one eye with glasses.
Key exclusion criteria (2 listed)
- Hyperopia ≥ 2.00 D
- Presence of visually-significant ocular condition besides refractive error
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| SpectaclesAlso: GlassesIntervention group children in middle school Year 1 will receive spectacles in December 2024. Assuming that the relevant effects of treatment (glasses wear) on the main study outcome are complete once examinations determining high school attendance are finished at the end of Middle School Year 3, Intervention participants will have undergone 32 months (December 2024 - July 2027) of treatment by the endpoint of the trial. | Device | Intervention |
Primary outcome
Academic high school attendance
Time frame: In July following completion of Year 3 of Middle School. This occurs after 32 months of participant followup.
Proportion of children who continue to academic high school as opposed to vocational high school or no additional schooling, assessed by systematically contacting parents, teachers and students to ascertain enrolment status
8 secondary outcomes
Compliance with spectacle wear
Time frame: After 12 months of participant followup
Blackboard use
Time frame: After 12 months of participant followup
Cost effectiveness of intervention.
Time frame: At study closeout, after 32 months of participant followup
Depression and Anxiety
Time frame: At baseline and 12 months post-treatment
Self Esteem
Time frame: At baseline and 12 months post-treatment
Emotional and behavioral problems
Time frame: At baseline and 12 months post-treatment
Progression of Shortsightedness
Time frame: At baseline and 12 months post-treatment
Parents' and students' attitude towards spectacle wear
Time frame: After baseline
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Sep 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Nathan Congdon, MD, MPH principal investigator
Queen's University, Belfast
3 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Spectacles in people with Refractive Errors, run by Queen's University, Belfast at 3 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 8 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in China, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Academic high school attendance (time frame: In July following completion of Year 3 of Middle School. This occurs after 32 months of participant followup.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Sep 2026.