ClinicalTrials.gg
Not yet recruitingNCT07706218PRECUpdated Jul 15, 2026

Cohort Study on Refractive Errors in Preschool Children

An observational study in Refractive Errors, sponsored by Zhongshan Ophthalmic Center, Sun Yat-sen University. Not yet recruiting at 1 site in China. Open to participants aged 0 Years to 6 Years. Per ClinicalTrials.gov, last updated 2026-07-15.

Sponsored by Zhongshan Ophthalmic Center, Sun Yat-sen University · Observational

Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
1,000
Ages
0 Years to 6 Years
Sex
All
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Study 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). 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.

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Conditions studied

  • Refractive Errors

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Keywords

  • Refractive error
  • preschool
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In context

Refractive Errors

420 studies on the registry are indexed under Refractive Errors; 59 are open to participants now.

This study's planned enrollment of 1,000 is above the median of 150 across 108 observational studies indexed under Refractive Errors.

Browse Refractive Errors studies →

Lead sponsor

Zhongshan Ophthalmic Center, Sun Yat-sen University is the lead sponsor of 164 studies on the registry; 80 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
0 Years to 6 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

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.

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Onset of refractive error occurs during preschool age (0-6 years old) supported by retrievable medical records;
  2. Spherical equivalent power ≤ -0.50 D or ≥ +3.00 D in any meridian;
  3. Legal guardians agree to participate and sign written .

Exclusion criteria

Exclusion Criteria:

Children unable to cooperate with examinations and follow-up visits.

Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

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Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
1,000 participants (estimated)
Target follow-up
3 Years
Patient registry
Yes

Groups and cohorts

  • Refractive error

    Refractive error in preschool children

06

What researchers measure

Primary outcomes

  1. 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.

    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

Secondary outcomes

  1. BCVA

    Visual Acuity Examination

    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

  2. Contrast Sensitivity

    CSF

    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

  3. SER

    Spherical Equivalent Refraction,Comprehensive index reflecting overall ocular refractive status, integrating myopia, hyperopia and astigmatism.

    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

  4. WES (Whole Exome Sequencing)

    Genetic sequencing results of all protein-coding regions to detect gene variants related to refractive disorders.

    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

  5. OCT

    OCT Imaging Findings

    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

07

Study locations

1 site
  • Zhongshan Ophthalmic Center Sun Yat-Sen University
    Guangdong, Guanzhou 510060, China
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References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jul 15, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT07706218
Collaborators
The People's Hospital of Ningxia
Responsible party
Sponsor
First posted
Jul 15, 2026
Start date
Aug 1, 2026 (estimated)
Primary completion
Dec 1, 2026 (estimated)
Completion
Dec 1, 2028 (estimated)
Last update
Jul 15, 2026

Study contacts

Xiao Yang
Contact
yangx_zoc@163.com
13760766303

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.

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