Time Outdoors as an Intervention for Myopia in Children

Study Overview
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Brief Summary
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The purpose of this study is to determine whether improved outdoor time has an effect on the onset and progression of myopia in children.

Detailed Description
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To evaluate the effect of increased time outdoors on the incidence of myopia in non-myopic children; To evaluate the effect of increased time outdoors on the progression of myopia in myopic children; To explore if there is dose-response effect of time outdoors on the incidence and progression of myopia.

Official Title
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Time Outdoors as an Intervention for Myopia in Children--School-based Randomized Controlled Study

Conditions
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Myopia

Intervention / Treatment
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* Behavioral: Outdoor activity 1
* Behavioral: Outdoor activity 2


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: at baseline be enrolled in grade 1 and 2 of primary schools; have a parent or guardian who is able to read and comprehend Mandarin and give informed consent as demonstrated by signing a record of informed consent; Children verbally consent when registration for examination Exclusion Criteria: Any systemic or ocular pathology that may affect the refractive error status of the eye; Strabismus and amblyopia; Intellectual disability; Using any anti-myopia treatments (orthokeratology, atropine, accommodation function training, acupuncture, auricular point sticking, progressive addition spectacle lenses or other anti-myopia contact lenses). Not suitable for inclusion in the study as deemed by the investigator.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 9 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br> | |
| Experimental: Outdoor Activity 1<br>40min outdoor time in total. | Behavioral: Outdoor activity 1<br>* 40-minute outdoor activity<br>|
| Experimental: Outdoor Activity 2<br>80min outdoor time in total | Behavioral: Outdoor activity 2<br>* Dose 1 plus an additional 40-minute outdoor activities during recesses<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cycloplegic refractive power（auto-refractor instrument） | The Cycloplegic refraction of all children are measured by auto-refractor(KR-8900, Topcon) | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length(IOL Master instrument) | The axial length of the eyeball are measured by IOL Master(version 5.02, Carl Zeiss). | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myopia, Outdoor time, Children, Intervention, Prevention