Cohort Study on Refractive Errors in Preschool Children (PREC)

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 Overview

Status

Not yet recruiting

Conditions

Study Type

Observational

Enrollment (Estimated)

1000

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Guanzhou
      • Guangdong, Guanzhou, China, 510060
        • Zhongshan Ophthalmic Center Sun Yat-Sen University
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

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.

Description

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 informed consent.

Exclusion Criteria:

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Refractive error
Refractive error in preschool children

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
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.
From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
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
Visual Acuity Examination
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
CSF
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
Spherical Equivalent Refraction,Comprehensive index reflecting overall ocular refractive status, integrating myopia, hyperopia and astigmatism.
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
Genetic sequencing results of all protein-coding regions to detect gene variants related to refractive disorders.
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
OCT Imaging Findings
From date of enrollment until the date of loss to follow-up from any cause, whichever came first, assessed up to 36 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

August 1, 2026

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 1, 2028

Study Registration Dates

First Submitted

July 9, 2026

First Submitted That Met QC Criteria

July 9, 2026

First Posted (Actual)

July 15, 2026

Study Record Updates

Last Update Posted (Actual)

July 15, 2026

Last Update Submitted That Met QC Criteria

July 9, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2023KYPJ340-2

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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