Vision Care
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Although eyeglasses have been considered a cost-effective way to combat myopia, the empirical evidence of its impacts on improving learning outcomes is inconsistent. This paper provides empirical evidence examining the effect of providing eyeglasses on academic performance between provinces with a different economic level in western China. Overall, we find a significant impact in Intention-to-Treat analysis and a large and significant local average treatment effect of providing free eyeglasses to students in the poor province but not in the other. The difference in impact between the two provinces is not a matter of experimental design, implementation, or partial compliance. Instead, we find that the lack of impact in the wealthier provinces is mainly due to less blackboard usage in class and wealthier households. Our study found that providing free eyeglasses to disadvantaged groups boosted their academic performance more than to their counterparts.

Authors
Kang Du
Huan Wang
Huan Wang
Yue Ma
Yue Ma
Hongyu Guan
Scott Rozelle
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Background

In rural China, children’s vision problems are very common, with many who would benefit from refractive correction not getting the care they need. This study examines whether a health information campaign that involves vision health education and a free trial of health product with free eyeglasses is effective at raising students’ awareness of myopia and promoting students’ eyeglasses usage.

Methods

We conducted an in-the-field randomized controlled experiment of a program providing vision health education and subsidized free eyeglasses to myopic children from 168 primary schools in rural Northwestern China in 2012.

Results

A total of 2189 students, mean age 10.5 years (49.3% male), participated in the baseline survey. At the baseline, the average correct response rate for visual knowledge among the sample students was 30.1%, and only 15% who needed eyeglasses used them. Seven months after intervention, the average correct response rate for vision knowledge were 48.5% and 48.3% in the education group and the education plus free eyeglasses group respectively, significantly higher than that of the control group. The rate of eyeglasses usage was 36% and 43% in the free eyeglasses group and the education plus free eyeglasses group respectively, significantly higher than that of the control group. The rate of eyeglasses compliance in the free eyeglasses group and the education plus free eyeglasses group was 19% and 26%, which also were significantly higher than the control group.

Conclusion

The information campaign combined with subsidized eyeglasses had a better effect both on vision knowledge and eyeglasses usage. The information campaign improved knowledge by providing the right information, and free eyeglasses changed the perceived utility and experience by the students using the product and getting benefits. Information and the free eyeglasses (subsidized) are complements.

Journal Publisher
Risk Management and Healthcare Policy
Authors
Yunyun Zhang
Hongyu Guan
Kang Du
Jin Zhao
Yaojiang Shi
Huan Wang
Huan Wang
Decai Wang
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Purpose

To study the factors determining spectacle-wear compliance and reasons for non-wear among students in rural China.

Methods

This study was based on a spectacle intervention trial among 162 schools in rural China. Students with refractive errors were randomly assigned to either a free or voucher group to receive spectacles at baseline. Spectacle-wear compliance was assessed through an unannounced follow-up 7 months after spectacles were distributed. Students not wearing spectacles were also asked their reasons for non-wear. The collected data underwent descriptive, bivariate, and logistic regression analyses.

Results

A total of 1904 students received spectacles at baseline, 1826 (95.9%) of whom were present at the 7-month follow-up. Among those students, 41.7% wore their spectacles. There was no significant difference in compliance rates between the free and voucher groups. Predictors of wearing spectacles at follow-up included older age (Odds ratio = 1.56, 95% CI: 1.12–2.19), the severity of refractive error (3.68, 2.23–6.07), wearing spectacles before baseline (3.91, 2.53–6.04) and having friends who wore spectacles (1.87, 1.32–2.63). When students could see the blackboard from their seats (0.68, 0.51–0.89) and thought that wearing spectacles was bad looking (0.76, 0.57–1.00), they were reluctant to wear spectacles. The two main reasons for non-wear were the widespread perception that wearing spectacles would weaken eyesight (32.8%) and the inconvenience of wearing spectacles during activities (23.6%).

Conclusions

The main reason that accounts for the low compliance of spectacle wear was misconceptions around spectacle. School-based spectacle programs should consider enhancing the compliance rates to maximize the benefits of spectacle wear.

Journal Publisher
Ophthalmic Epidemiology
Authors
Kang Du
Jiaqi Zhu
Hongyu Guan
Yunyun Zhang
Huan Wang
Huan Wang
Decai Wang
Yaojiang Shi
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The cost-effectiveness of policies providing subsidized health goods is often compromised by limited use of the goods provided. Through a randomized trial involving 251 primary schools in western China, we tested two approaches to improve the cost-effectiveness of a program distributing free eyeglasses to myopic children. Relative to delivery of free eyeglasses to schools, we find that providing vouchers redeemable in local optical shops modestly improved the targeting of eyeglasses to those who would use them without reducing effective coverage. Information provided through a health education campaign increased eyeglass use when eyeglasses were delivered to schools, but had no effect when requiring voucher redemption or when families were only given a prescription for eyeglasses to be purchased on the market. Though most expensive, free delivery to schools with a health education campaign was the most socially cost-effective approach tested and increased effective coverage of eyeglasses by 18.5 percentage points after seven months.

Journal Publisher
Science Direct
Authors
Sean Sylvia
Xiaochen Ma
Yaojiang Shi
Scott Rozelle
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Background

Despite rising incomes and rapid economic growth, there remains a significant gender gap in health outcomes among rural children in China. This study examines whether the gender gap in child health is related to the behavior of caregivers when seeking healthcare, and whether healthcare subsidies help to bridge the gender gap in rural health outcomes.

Methods

Focusing on vision care specifically, we draw on data from a randomized controlled trial of 13,100 children in Gansu and Shaanxi provinces in China that provided subsidized eyeglasses to myopic children in one set of schools (henceforth, referred to as the treatment schools) and provided prescription information but not subsidized eyeglasses to myopic children in another set of schools (control schools).

Results

The baseline results reveal that while female students generally have worse vision than male students, they are significantly less likely than male students to be taken by their caregivers to a vision exam. The experimental results indicate, however, that caregivers respond positively to both health information and subsidized healthcare, regardless of the gender of their children. When prescription information is paired with a subsidy voucher for healthcare (a free pair of eyeglasses), the uptake rate rises dramatically.

Conclusions

The gender gap in healthcare can be minimized by implementing subsidized healthcare policies.

Journal Publisher
International Journal for Equity in Health
Authors
Huan Wang
Huan Wang
Claire Cousineau
Yingjie Fan
Sarah-Eve Dill
Matthew Boswell
Matthew Boswell
Scott Rozelle
Xiaochen Ma
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Purpose: To determine the prevalence of visual impairment and glasses ownership among Han Chinese and Hui minority junior high school children in Ningxia Hui Autonomous Region, China. 

Design: Population-based cross-sectional study. 

Methods: Vision screening was conducted on 20,376 children (age 12–15 years) in all 124 rural junior high schools in Ningxia. Personal and family characteristics, glasses ownership, and academic performance were assessed through a survey questionnaire and standardized mathematics test, respectively. 

Results: The prevalence of visual acuity (VA) ≤6/12 in either eye was significantly higher among Han (54.5%) than Hui (45.2%) children (P<0.001), and was significantly positively associated with age, female sex, Han ethnicity, parental outmigration for work, shorter time spent outside during recess, shorter time spent watching television and higher time spent studying. Among children with VA≤6/12 in both eyes, only 56.8% of Han and 41.5% of Hui children had glasses (P<0.001). Glasses ownership was significantly associated with worse vision, greater family wealth, female sex, higher test scores, age, parental outmigration for work, understanding of myopia and glasses, higher time spent studying and Han ethnicity. 

Conclusion: One of the first of its kind, this report on Han and Hui ethnic schoolchildren confirms a high prevalence of visual impairment among both populations, but slightly higher among the Han. Both groups, especially the Hui, have low rates of glasses ownership. Future interventions and policies designed to improve glasses usage should focus on populations with lower incomes and seek to correct erroneous beliefs about the safety of glasses and efficacy of traditional eye exercises.

Journal Publisher
PLOS ONE
Authors
Huan Wang
Huan Wang
Brandon Barket
Sharon Du
Dimitris Friesen
Ezra Kohrman
Esther Tok
Baixiang Xiao
Wenyong Huang
Ving Fai Chan
Graeme MacKenzie
Nathan Congdon
Nathan Congdon
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This paper examines the external validity of health intervention by comparing the impacts of providing free eyeglasses on the educational performance of nearsighted children in two settings: rural public schools in Western China and urban private migrant schools in Eastern China. The intervention significantly improves educational outcomes by 0.14 standard deviations in math in rural public schools but not in private migrant schools. The difference in measured impacts is due in part to lower quality schooling in migrant schools in Eastern China. Our findings show that only when school is providing a quality education, health interventions might increase student learnings.
Journal Publisher
Journal of Development Effectiveness
Authors
Xiaochen Ma
Huan Wang
Huan Wang
Yaojiang Shi
Sean Sylvia
Lei Wang
Yiwei Qian
Scott Rozelle
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Purpose To describe changes in the prevalence of visual impairment and glasses ownership with age and as associated with income and population density for visual impairment among rural and urban migrant Chinese students.

Design Meta-analysis of 12 cross-sectional, school-based studies conducted between 2012 and 2017.

Setting Rural and urban migrant schools in seven Chinese provinces.

Participants A total of 83 273 rural and urban migrant Chinese students aged 6–17 years.

Results Prevalence of visual impairment (uncorrected visual acuity ≤6/12 in either eye) rose from 19.0% at age 6 to 66.9% at 17, with the overall age-adjusted prevalence higher for girls (35.8%) than for boys (30.1%, p<0.001). The rate of glasses ownership among students who needed them increased from 13.0% at age 6 to 63.9% (p<0.001) at 17 and was significantly higher for girls (37.0%) than boys (34.7%, p<0.001). The unmet need for glasses as a proportion of the student population peaked in junior high school (31.8%). A 1% increase in per capita gross domestic product was associated with a 4.45% rise in uncorrected visual acuity (R2=0.057, p=0.020). Population density was significantly associated with glasses ownership among children (R2=0.359, p=0.012). A 1% population density increase was associated with an increase in the glasses ownership rate of 6.83%.

Conclusion Efforts are needed to improve vision screening coverage in China’s schools, particularly junior high schools, as this is when many rural children leave school and glasses coverage is lowest.

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BMJ Ophthalmology
Authors
Yue Ma
Yue Ma
Xinwu Zhang
Fei He
Xiaochen Ma
Nathan Rose
Alexis Medina
Nathan Congdon
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Objective: To assess the effect of free eyeglasses provision on visual acuity among middle school students in northwestern rural China.

Methods and analysis: Among 31 middle schools randomly selected from 47 middle schools in northwestern rural China, students were randomly allocated by school to one of two interventions: free eyeglasses (intervention group), and eyeglasses prescriptions given only to the parents (control group). The main outcome of this study is uncorrected visual acuity after 9 months, adjusted for baseline visual acuity.

Results: Among 2095 students from 31 middle schools, 995 (47.5%) failed the visual acuity screening, 515 (51.8%, 15 schools) of which were randomly assigned to the intervention group, with the remaining 480 students (48.2%, 16 schools) assigned to the control group. Among these, a total of 910 students were followed up and analysed. Endline eyeglasses wear in the intervention group was 44%, and 36% in the control group. Endline visual acuity of students in the intervention group was significantly better than students in the control group, adjusting for other variables (0.045 LogMAR units, 95% CI 0.006 to 0.084, equivalent to 0.45 lines, p=0.027), and insignificantly better only for baseline visual acuity (difference of 0.008 LogMAR units, 95% CI −0.018 to 0.034, equivalent to 0.08 lines).

Conclusion: We found no evidence that receiving free eyeglasses worsened visual acuity among middle school students in northwestern rural China.

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BMJ Open Ophthalmology
Authors
Yue Ma
Xinwu Zhang
Haoyang Li
Dimitris Friesen
Ming Zhou
Nathan Congdon
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Objective: To estimate the effect of providing free spectacles on uncorrected visual acuity (VA) among urban migrant Chinese school children. Design Exploratory analysis from a parallel cluster-randomised clinical trial.

Methods: After baseline survey and VA screening, eligible children were randomised by school to receive one of the two interventions: free glasses and a teacher incentive (tablet computer if ≥80% of children given glasses were wearing them on un-announced examination) (treatment group) or glasses prescription and letter to parents (control group). The primary outcome was uncorrected logarithm of the minimal angle of resolution (LogMAR) VA at study closeout, adjusted for baseline uncorrected VA.

Results: Among 4376 randomly selected children, 728 (16.6%, mean age 10.9 years, 51.0% boys) at 94 schools failed VA screening and met eligibility criteria. Of these, 358 children (49.2%) at 47 schools were randomised to treatment and 370 children (50.8%) at 47 schools to control. Among these, 679 children (93.3%) completed follow-up and underwent analysis. Spectacle wear in the treatment and control groups was 68.3% and 29.3%(p<0.001), respectively. Uncorrected final VA for eyes of treatment children was significantly better than control children, adjusting only for baseline VA (difference of 0.039 LogMAR units, 95% CI: 0.008, 0.070, equivalent to 0.39 lines, p=0.014) or baseline VA and other baseline factors (0.040 LogMAR units, 95% CI 0.007 to 0.074, equivalent to 0.40 lines, p=0.020).

Conclusion: We found no evidence that spectacles wear worsens children’s uncorrected VA among urban migrant Chinese school children.

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British Journal of Opthalmology
Authors
Xinwu Zhang
Ming Zhou
Haiqing Zhang
Xiuqing Wang
Ling Jin
Kovin Naidoo
Hasan Minto
Haidong Zou
Nathan Congdon
Yue Ma
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