Zhaoqing Myopia Study

A Prospective School-based Study of Myopia in Children in Southern China

Myopia is a common cause of vision loss, being particularly prevalent in children in East and Southeast Asia. The investigators will assess prevalence and incidence of myopia, identify digital biomarkers associated with myopia, and validate algorithms for the detection and/or predition of myopia and other ocular abnormalities in school-aged children in both urban and rural settings in Southern China.

Study Overview

• Status: Unknown
• Conditions: Myopia
• Intervention / Treatment: Diagnostic test: Ophthalmic examinations; Device: Wearable devices

Detailed Description

Myopia is a common cause of vision loss, being particularly prevalent in East and Southeast Asia. It is still not entirely clear whether and how visual experience in an urban environment with less outdoor exposure could have an impact on the development and progression of myopia. Zhaoqing has a relatively stable population of 4,084,600, which are representative of the Chinese population in term of demographic and socioeconomic characteristics.

Therefore, the investigators will conduct a longitudinal cohort study in both urban and rural settings to examine prevalence and incidence of myopia, identify digital biomarkers associated with myopia, and validate algorithms for the detection and/or predition of incidence and progression of myopia and other ocular abnormalities in school-aged children in Zhaoqing.

• Study Type: Observational
• Enrollment (Anticipated): 4000

Contacts and Locations

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510000
      • Recruiting
      • Zhognshan Ophthalmic Center, Sun Yat-sen University
    • Zhaoqing, Guangdong, China
      • Recruiting
      • Schools
      • Contact: Yingfeng Zheng; Email: zhyfeng@mail.sysu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 7 years (Child)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

All first-grade students from 10 primary schools in urban counties, and from 10 primary schools in rural counties, Zhaoqing city.

Description

Inclusion Criteria:

• All first-grade students from 10 primary schools in urban counties, and from 10 primary schools in rural counties, Zhaoqing city.

Exclusion Criteria:

• No.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Students in urban counties; All first-grade students in urban counties will undergo anthropometry and ophthalmic examination, and be required to complete questionnaires and wear wearable devices to collect environmental information and daily activities.	Diagnostic test: Ophthalmic examinations; Ophthalmic examinations include visual acuity, cover test and ocular dominance, noncycloplegic autorefraction, cycloplegia, ocular biometric measurements, cycloplegic auto-refraction, subjective refraction, and anterior and posterior segment examination.; Device: Wearable devices; Physical activity, light intensity, and visual information will be measured with wearable devices.
Students in rural counties; All first-grade students in rural counties will undergo anthropometry and ophthalmic examination, and be required to complete questionnaires and wear wearable devices to collect environmental information and daily activities.	Diagnostic test: Ophthalmic examinations; Ophthalmic examinations include visual acuity, cover test and ocular dominance, noncycloplegic autorefraction, cycloplegia, ocular biometric measurements, cycloplegic auto-refraction, subjective refraction, and anterior and posterior segment examination.; Device: Wearable devices; Physical activity, light intensity, and visual information will be measured with wearable devices.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incident myopia	Incident myopia is defined as myopia detected during follow up among those without myopia at baseline. Myopia is defined as any eye's SER (sphere + 1/2 cylinder) of at least -0.5 diopters (D).	3 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of myopia	Myopia is defined as any eye's SER (sphere + 1/2 cylinder) of at least -0.5 diopters (D).	baseline
Change in axial length	Axial length will be measured with a non-contact optical device.	1 year, 2 years, 3 years
Prevalence of amblyopia, strabismus and other ocular abnormalities	Cover-uncover tests will be performed to detect strabismus. Any ocular abnormalities, including corneal opacities, lens opacities, and retinal diseases will be recorded based on slit lamp, direct ophthalmoscopic and/or mobile phone video examination. Participants with an uncorrected visual acuity 6/7.5 or worse with undergo subjective refraction to identify amblyopia.	baseline
Area under the receiver operating characteristic curve of the deep learning algorithm for the prediction of incident myopia	The investigators will estimate the area under the receiver operating characteristic curve of the deep learning algorithm for the prediction of incident myopia.	1 year
Sensitivity and specificity of the deep learning algorithm for the prediction of incident myopia	The investigators will estimate sensitivity and specificity of the deep learning algorithm for the prediction of incident myopia.	1 year
Area under the receiver operating characteristic curve of the deep learning algorithm for the prediction of fast progressing myope	The investigators will estimate the area under the receiver operating characteristic curve of the deep learning algorithm for the prediction of fast progressing myope (a change in SER of 0.75D or more per year).	1 year
Sensitivity and specificity of the deep learning algorithm for the prediction of fast progressing myope	The investigators will estimate the sensitivity and specificity of the deep learning algorithm for the prediction of fast progressing myope (a change in SER of 0.75D or more per year). Cycloplegic spherical refraction changes measured by an auto-refractometer will be used as the indicator of myopia progression.	1 year
Area under the receiver operating characteristic curve of the diagnostic algorithm in identifying abnormal vision screening result	The investigators will estimate the area under the receiver operating characteristic curve of the diagnostic algorithm in identifying abnormal vision screening result (e.g., abnormal eye lid, abnormal cornea, and strabismus detected with mobile devices).	baseline
Sensitivity and specificity of the diagnostic algorithm in identifying abnormal vision screening result	The investigators will estimate the sensitivity and specificity of the diagnostic algorithm in identifying abnormal vision screening result (e.g., abnormal eye lid, abnormal cornea, and strabismus detected with mobile devices).	baseline
Post-vision screening referral uptake	Any referral uptake will be confirmed by telephone follow-up.	3 months

Collaborators and Investigators

• Sponsor: Sun Yat-sen University

Publications and helpful links

General Publications

• Morgan IG, Ohno-Matsui K, Saw SM. Myopia. Lancet. 2012 May 5;379(9827):1739-48. doi: 10.1016/S0140-6736(12)60272-4.
• Zadnik K, Mutti DO. Outdoor Activity Protects Against Childhood Myopia-Let the Sun Shine In. JAMA Pediatr. 2019 May 1;173(5):415-416. doi: 10.1001/jamapediatrics.2019.0278. No abstract available.
• Ojaimi E, Rose KA, Smith W, Morgan IG, Martin FJ, Mitchell P. Methods for a population-based study of myopia and other eye conditions in school children: the Sydney Myopia Study. Ophthalmic Epidemiol. 2005 Feb;12(1):59-69. doi: 10.1080/09286580490921296.
• Li SM, Liu LR, Li SY, Ji YZ, Fu J, Wang Y, Li H, Zhu BD, Yang Z, Li L, Chen W, Kang MT, Zhang FJ, Zhan SY, Wang NL, Mitchell P; Anyang Childhood Eye Study Group. Design, methodology and baseline data of a school-based cohort study in Central China: the Anyang Childhood Eye Study. Ophthalmic Epidemiol. 2013 Dec;20(6):348-59. doi: 10.3109/09286586.2013.842596. Epub 2013 Oct 25.
• He M, Zheng Y, Xiang F. Prevalence of myopia in urban and rural children in mainland China. Optom Vis Sci. 2009 Jan;86(1):40-4. doi: 10.1097/OPX.0b013e3181940719.
• Negrel AD, Maul E, Pokharel GP, Zhao J, Ellwein LB. Refractive Error Study in Children: sampling and measurement methods for a multi-country survey. Am J Ophthalmol. 2000 Apr;129(4):421-6. doi: 10.1016/s0002-9394(99)00455-9.
• Chen X, Ye G, Zhong Y, Jin L, Liang X, Zeng Y, Zheng Y, Lan M, Liu Y. Prevalence, incidence, and risk factors for myopia among urban and rural children in southern China: protocol for a school-based cohort study. BMJ Open. 2021 Nov 5;11(11):e049846. doi: 10.1136/bmjopen-2021-049846.

Study record dates

Study Major Dates

• Study Start (Actual): December 14, 2019
• Primary Completion (Anticipated): February 2, 2023
• Study Completion (Anticipated): February 2, 2023

Study Registration Dates

• First Submitted: December 28, 2019
• First Submitted That Met QC Criteria: January 3, 2020
• First Posted (Actual): January 6, 2020

Study Record Updates

• Last Update Posted (Actual): March 17, 2020
• Last Update Submitted That Met QC Criteria: March 13, 2020
• Last Verified: March 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Myopia
• Other Study ID Numbers: 2019KYPJ171

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No