Effect of Increasing Time Spent Outdoors on Myopia Prevention in School-Aged Children in Northeast China

Development and Application of Appropriate Technology for Myopia Prevention and Control

The purpose of this study is to develop a school-based intervention aimed at prevent the onset and development of myopia among school aged children by increasing time spent outdoors in northeast China.

Study Overview

• Status: Completed
• Conditions: Myopia
• Intervention / Treatment: Behavioral: increasing time spent outdoors

Detailed Description

The purpose of this study is to develop a school-based intervention aimed at prevent the onset and development of myopia among school aged children by increasing time spent outdoors among elementary and secondary school students in northeast China. It is expected that the results will provide evidences for policy-makers and school healthcare providers for their school children myopia prevention.

• Study Type: Interventional
• Enrollment (Actual): 3521
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 14 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Grade of 1 to 5 in elementary schools and grade of 7 to 8 in secondary schools.

Exclusion Criteria:

• Visual defect or other eye diseases; wearing orthokeratology; refractive surgery history.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: intervention group; The intervention group undertook interventions by increasing time spent outdoors. The interventions composed of performing two additional recess program lasting 30 minutes outside the classroom that encouraged children to go outside for outdoor activities during recess in both the morning and afternoon during school days within a intervention period of 1 school year.	Behavioral: increasing time spent outdoors; The intervention group undertook interventions by increasing time spent outdoors. The interventions composed of performing two additional recess program lasting 30 minutes outside the classroom that encouraged children to go outside for outdoor activities during recess in both the morning and afternoon during school days within a intervention period of 1 school year.
No Intervention: control group; The control school did not have any interventions.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in uncorrected visual acuity	Uncorrected visual acuity (UCVA) was measured for the right eye, then the left eye, with a E Standard Logarithm Vision Acuity Chart (GB11533-2011) in 5-grade notation (5- LogMAR), with illumination of the chart around 500lx. If one of the eyes UCVA was less than 5.0, then tests with combined lenses were conducted among the poor eye-sighted for confirming the types of ametropia (normal, myopia, hyperopia or other eye diseases)．All the measurements were recorded.	Baseline, Month 6, Month 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Questionnaire survey	The parents and children underwent an interview together. The questionnaire included questions on children's gender, ethnicity, region of habitation; questions on parental education level, the monthly family income and whether the parents were myopic or not;. The interview also included questions on the amount of time spent for learning (reading or writing), screen time (television, computer, etc) and time spent outdoors after school in recent 7 days.	Baseline
Changes in ocular biometric parameters	A random subsample (12.8%) underwent cycloplegia. After ensuring that there was no risk for a medical mydriasis, cycloplegia was performed at baseline and intervention after 1 year in the Shenyang Aier Ophthalmology Hospital, respectively. Ocular biometric parameters (axial length, corneal curvature, anterior chamber depth and IOP) were measured in both eyes of all participants. Axial length, corneal curvature and anterior chamber depth were measured with IOL Master (intraoeular len master, IOL. Master) (Carl Zeiss Meditex, Jena, Germany); Intraocular pressure (IOP) measurement was obtained using a non-contact tonometry (NT-510, NIDEK, Gamagori, Japan). Cycloplegia was achieved by 0.5% tropicamide eye drops. Six drops of tropicamide 0.5% were administered at 5-minute intervals for both eyes. Refractometry was performed 20 minutes after the last cycle of cycloplegic eye drops by retinoscopy (YZ-24, Suzhou, China).	Baseline, Month 12

Collaborators and Investigators

• Sponsor: Anhui Medical University
• Investigators: Study Director: Fangbiao Tao, PhD, Department of Maternal, Child and Maternal Health, School of Public Health, Anhui Medical University

Publications and helpful links

General Publications

• Jin JX, Hua WJ, Jiang X, Wu XY, Yang JW, Gao GP, Fang Y, Pei CL, Wang S, Zhang JZ, Tao LM, Tao FB. Effect of outdoor activity on myopia onset and progression in school-aged children in northeast China: the Sujiatun Eye Care Study. BMC Ophthalmol. 2015 Jul 9;15:73. doi: 10.1186/s12886-015-0052-9.

Study record dates

Study Major Dates

• Study Start: November 1, 2012
• Primary Completion (Actual): November 1, 2013
• Study Completion (Actual): February 1, 2014

Study Registration Dates

• First Submitted: October 19, 2014
• First Submitted That Met QC Criteria: October 21, 2014
• First Posted (Estimate): October 22, 2014

Study Record Updates

• Last Update Posted (Estimate): October 23, 2014
• Last Update Submitted That Met QC Criteria: October 22, 2014
• Last Verified: October 1, 2014

More Information

Terms related to this study

• Keywords: Physical activity; Intervention Studies; Schoolchildren; Vision, Ocular
• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Myopia
• Other Study ID Numbers: 2013001