Refractive ErrorsPRECNCT07706218
Cohort Study on Refractive Errors in Preschool Children
An observational study of Refractive Errors, run by Zhongshan Ophthalmic Center, Sun Yat-sen University at 1 site in China.
Trial summary
Refractive error is a common visual disorder encompassing myopia, hyperopia, astigmatism and other subtypes. Refractive error in preschool children refers to refractive abnormalities occurring during the preschool period (0-6 years old). Read more about this study
- Who is it for?
- Ages 0 to 6 years
- Conditions the study is for
- Refractive Errors
- How many people
- 1,000 participants
- Where
- 1 siteChina
- Study dates
- 1 Aug 2026to 1 Dec 2028
- How long will I take part?
- 3 Years
- Phase
- Observational
- 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 0 to 6 years
- All sexes
- No healthy volunteers
- Child
Study population: This study enrolls preschool children aged 0-6 years with refractive errors as the observation group. Eligible subjects meet the following inclusion criteria: refractive error onset during preschool period confirmed by available medical records, spherical power ≤ -0.50 D or ≥ +3.00 D in any meridian, and written informed consent provided by legal guardians. Children who cannot cooperate with ophthalmic examinations and long-term follow-up will be excluded.
Who may be able to join
- Onset of refractive error occurs during preschool age (0-6 years old) supported by retrievable medical records;
- Spherical equivalent power ≤ -0.50 D or ≥ +3.00 D in any meridian;
- Legal guardians agree to participate and sign written informed consent.
Who cannot join
- Children unable to cooperate with examinations and follow-up visits.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site
Zhongshan Ophthalmic Center Sun Yat-Sen University
Guangdong, Guanzhou, 510060
Xiao Yang, 13760766303, yangx_zoc@163.com
About this study
Refractive error is a common visual disorder encompassing myopia, hyperopia, astigmatism and other subtypes. Refractive error in preschool children refers to refractive abnormalities occurring during the preschool period (0-6 years old). Studies conducted across diverse regions and populations report that the prevalence of refractive error among preschool children ranges approximately from 10% to 30%, with this proportion showing a gradual upward trend in recent years. Existing evidence suggests that preschool refractive status is correlated with multiple ocular and systemic diseases. Furthermore, the preschool years represent a highly sensitive window for children's visual development; uncorrected refractive errors at this stage can disrupt visual maturation and induce permanent visual impairment. Accordingly, identifying the full spectrum of comorbidities associated with preschool refractive error, alongside implementing early diagnosis and intervention, is clinically critical.
Nevertheless, substantial challenges persist in the clinical management of preschool refractive errors: the complete comorbidity spectrum remains undefined, its natural history has not been fully elucidated, and high-quality evidence-based guidelines for refractive correction and visual rehabilitation are lacking. Establishing a prospective cohort of preschool children with refractive errors is therefore of great significance for clarifying disease progression and risk factors, generating evidence for standardized refractive interventions and visual rehabilitation protocols, and ultimately preventing visual impairment and improving quality of life in this vulnerable pediatric population.
Our research team has previously completed preliminary investigations characterizing myopia in preschoolers. Building on this foundational work, we aim to construct a dedicated cohort of preschool children with refractive errors to delineate the natural history, progression risks and comorbidity profiles of preschool refractive error, and explore effective refractive correction and visual rehabilitation approaches for affected young children.
- Conditions
- Refractive Errors
- Keywords
- Refractive error, preschool
- Medical subject headings
- Refractive Errors
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Refractive error | Refractive error in preschool children |
What is being measured
The primary outcome is the main question the study is designed to answer.
Ocular Biometry Parameters
A set of objective ocular structural measurements mainly including axial length (AL), alongside corneal curvature, anterior chamber depth, lens thickness and vitreous chamber depth. Axial length, the core indicator in this study, refers to the linear distance from the anterior corneal surface to the retinal pigment epithelium, which is closely associated with the onset and progression of refractive errors in preschool children. All biometric indices will be measured using standardized ophthalmic biometry equipment at each follow-up visit to dynamically observe the developmental rules of ocular dimensions and their correlation with refractive status.
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
Secondary outcomes (5)
BCVA
Visual Acuity Examination
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
Contrast Sensitivity
CSF
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
SER
Spherical Equivalent Refraction，Comprehensive index reflecting overall ocular refractive status, integrating myopia, hyperopia and astigmatism.
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
WES (Whole Exome Sequencing)
Genetic sequencing results of all protein-coding regions to detect gene variants related to refractive disorders.
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
OCT
OCT Imaging Findings
Measured: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jul 2026
- Study start1 Aug 2026 (estimated)
- Primary completion1 Dec 2026 (estimated)
- Study completion1 Dec 2028 (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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 1,000 participants (estimated)
- Target duration
- 3 Years
Sponsor and investigators
- Lead sponsor
- Zhongshan Ophthalmic Center, Sun Yat-sen University
- Sponsor type
- University, hospital or other
- Collaborators
- The People's Hospital of Ningxia
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07706218
- Sponsor's protocol ID
- 2023KYPJ340-2
- Acronym
- PREC
- Status last verified
- Jul 2026
- First submitted
- 9 Jul 2026
- Last updated
- 15 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 15 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Cohort Study on Refractive Errors in Preschool Children
- ClinicalTrials.gov ID
- NCT07706218
- Acronym / sponsor ID
- PREC / 2023KYPJ340-2
- Conditions
- Refractive Errors
- Keywords
- Refractive error, preschool
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 1,000 participants (estimated)
- Lead sponsor
- Zhongshan Ophthalmic Center, Sun Yat-sen UniversityUniversity, hospital or other
- Collaborators
- The People's Hospital of Ningxia
- Study start
- 1 Aug 2026 (estimated)
- Primary completion
- 1 Dec 2026 (estimated)
- Study completion
- 1 Dec 2028 (estimated)
- First posted
- 15 Jul 2026 (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.
Refractive error is a common visual disorder encompassing myopia, hyperopia, astigmatism and other subtypes. Refractive error in preschool children refers to refractive abnormalities occurring during the preschool period (0-6 years old). Studies conducted across diverse regions and populations report that the prevalence of refractive error among preschool children ranges approximately from 10% to 30%, with this proportion showing a gradual upward trend in recent years. Existing evidence suggests that preschool refractive status is correlated with multiple ocular and systemic diseases. Furthermore, the preschool years represent a highly sensitive window for children's visual development; uncorrected refractive errors at this stage can disrupt visual maturation and induce permanent visual impairment. Accordingly, identifying the full spectrum of comorbidities associated with preschool refractive error, alongside implementing early diagnosis and intervention, is clinically critical.
Nevertheless, substantial challenges persist in the clinical management of preschool refractive errors: the complete comorbidity spectrum remains undefined, its natural history has not been fully elucidated, and high-quality evidence-based guidelines for refractive correction and visual rehabilitation are lacking. Establishing a prospective cohort of preschool children with refractive errors is therefore of great significance for clarifying disease progression and risk factors, generating evidence for standardized refractive interventions and visual rehabilitation protocols, and ultimately preventing visual impairment and improving quality of life in this vulnerable pediatric population.
Our research team has previously completed preliminary investigations characterizing myopia in preschoolers. Building on this foundational work, we aim to construct a dedicated cohort of preschool children with refractive errors to delineate the natural history, progression risks and comorbidity profiles of preschool refractive error, and explore effective refractive correction and visual rehabilitation approaches for affected young children.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 3 Years
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Refractive error | – | –Refractive error in preschool children |
Who may qualify
- Ages
- 0 to 6 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
- Study population
- This study enrolls preschool children aged 0-6 years with refractive errors as the observation group. Eligible subjects meet the following inclusion criteria: refractive error onset during preschool period confirmed by available medical records, spherical power ≤ -0.50 D or ≥ +3.00 D in any meridian, and written informed consent provided by legal guardians. Children who cannot cooperate with ophthalmic examinations and long-term follow-up will be excluded.
Key inclusion criteria (3 listed)
- Onset of refractive error occurs during preschool age (0-6 years old) supported by retrievable medical records;
- Spherical equivalent power ≤ -0.50 D or ≥ +3.00 D in any meridian;
- Legal guardians agree to participate and sign written informed consent.
Key exclusion criteria (1 listed)
- Children unable to cooperate with examinations and follow-up visits.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Ocular Biometry Parameters
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
A set of objective ocular structural measurements mainly including axial length (AL), alongside corneal curvature, anterior chamber depth, lens thickness and vitreous chamber depth. Axial length, the core indicator in this study, refers to the linear distance from the anterior corneal surface to the retinal pigment epithelium, which is closely associated with the onset and progression of refractive errors in preschool children. All biometric indices will be measured using standardized ophthalmic biometry equipment at each follow-up visit to dynamically observe the developmental rules of ocular dimensions and their correlation with refractive status.
5 secondary outcomes
BCVA
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
Contrast Sensitivity
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
SER
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
WES (Whole Exome Sequencing)
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
OCT
Time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months
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 15 Jul 2026.
- Individual participant dataSharing planned: Undecided
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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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Refractive Errors, run by Zhongshan Ophthalmic Center, Sun Yat-sen University at 1 site in China.
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 3 inclusion and 1 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: opening soon, as of the sponsor's last update on 15 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. 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?
Contact Xiao Yang (13760766303, yangx_zoc@163.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Ocular Biometry Parameters (time frame: From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months). 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 15 Jul 2026.