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.

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.

Background
Daily “eye exercises,” massaging of periocular acupuncture pressure points, have been part of China’s national vision care policy in schools for some 50 years. However, the effect of eye exercises on myopia progression and eyeglasses wear has not been definitively investigated. This study evaluates the effectiveness of eye exercises on visual acuity and the propensity of rural children to wear eyeglasses.

Methods
Cohort study in 252 randomly-selected rural schools with baseline in September 2012 and follow up surveys 9 and 21 months later. Outcomes were assessed using propensity-score matching (PSM), multivariate linear regression and logistic regression to adjust for differences between children performing and not performing eye exercises.

Results
Among 19,934 children randomly selected for screening, 2374 myopic (spherical equivalent refractive error ≤ − 0.5 diopters in either eye) children (11.9%, mean age 10.5 [Standard Error 1.08] years, 48.5% boys) had VA in either eye ≤6/12 without eyeglasses correctable to > 6/12 with eyeglasses. Among these who completed the 21-month follow up, 1217 (58.2%) children reported practicing eye exercises on school days and 874 (41.8%) did not. After propensity-score matching, 1652 (79%) children were matched: 826 (50%) in the Eye Exercises group and 826 (50%) in the No Exercise group. Performing eye exercises was not associated with change in LogMAR uncorrected visual acuity and wear of eyeglasses, using either logistic regression or PSM at 9 or 21 months.

Conclusions
We found no evidence for an effect of eye exercises on change in vision or eyeglasses wear.

Providing vision care to students in rural areas may serve the purpose of poverty alleviation by improving education and health. This study aims to provide a comprehensive review of myopia studies among rural students in China and offer policy recommendations for the national myopia prevention and control plan under “Targeted poverty alleviation through education”. The results show that in rural China, 25% of primary school students and 50% of lower secondary school students are myopic. Moreover, more than 70% of rural myopic students suffer from uncorrected vision, which negatively affects student academic performance and mental health. Correcting myopia also has a significant positive impact on student academic achievement. Studies show that vision screening is an effective way to identify myopia among rural students. Providing subsidies for the families of myopic students to obtain eyeglasses, and providing incentives to teachers, can significantly improve the uptake and usage rates of eyeglasses. A county hospital-based vision center may be an effective platform for reducing children's visual impairment in rural China.

PURPOSE:
To explore the accuracy and cost-effectiveness of three vision screening models among preschool children in rural China.

METHODS:
Vision screening was carried out among children aged 4-5 years in 65 preschools in two counties in Northwest China, using Crowded Single Lea Symbols to test visual acuity. Children were assigned randomly by school to one of three screening models: screening by teachers (15 schools, 1835 children), local optometrists (30 schools, 1718 children) or volunteers (20 schools, 2183 children). Children identifying ≥2 symbols incorrectly in either eye failed screening. Accuracy of screening was compared with screenings executed by experienced optometrists among 141 children selected randomly from the three screening models. Direct and indirect costs for each model were assessed. Costs to detect a true case failed screening were estimated.

RESULTS:
The sensitivity for three models ranged from 76.9% to 87.5%, specificity from 84.9% to 86.7% and standardized positive predictive value from 83.7% to 85.7%. None differed significantly between models. The costs per case detected were $37.53, $59.14 and $52.19 for the teachers, local optometrists and volunteers. In producing the cost estimates for teacher screening and local optometrist screening models, we used a salary payment that was identical for both models (with the salary being equal to that of the optometrist). The teacher screening model was the most cost-effective.

CONCLUSION:
Accuracy of screening by teachers, local optometrists and volunteers was the same in this setting, but the use of teachers was most cost-effective, reducing the cost per case detected by almost 40%.

PURPOSE:
To assess the prevalence of visual impairment and spectacles ownership among academic and vocational upper secondary school students in rural China.

METHODS:
This cross-sectional study included 5583 students from four academic upper secondary schools (AUSSs) and two vocational upper secondary schools (VUSSs) in Mei and Qianyang counties, Baoji Prefecture, Shaanxi Province. In March and April 2016, students underwent assessment of visual acuity (VA) and completed a questionnaire regarding spectacles use and family characteristics. Students with visual impairment (presenting VA ≤6/12 in the better eye) and students needing spectacles (uncorrected VA ≤6/12 in the better eye, which could be improved to >6/12 with refraction) were identified.

RESULTS:
Among 5583 students (54% boys, mean age 16.4±1.0 years) in grades 10 and grade 11 attending AUSSs (n=4549) and VUSSs (n=1034), visual impairment was detected in 4026 students. Among the AUSS students, 3425 (75%) needed spectacles; 2551 (75%) had them. Among the VUSS students, 601 (58%) needed spectacles; this proportion was significantly smaller (P=0.004), as was the proportion who had spectacles (n=212, 35%, P<0.001), compared with the AUSS students. Multivariate analysis showed that ownership of spectacles among children who needed them was associated with worse uncorrected VA (P<0.001), male sex (P<0.001), and residence in an urban area (P<0.034). Spectacles ownership was also strongly associated with AUSS education (P<0.001).

CONCLUSION:
There is a high rate of unmet need in visual care among upper secondary school students. Lack of spectacles ownership among children who needed them was significantly associated with VUSS education.

KEYWORDS:
China; Eyeglasses; Rural population; Students; Vision disorders

Background
To assess the prevalence of visual impairment and rate of wearing spectacles in schools for children of migrant workers in Shanghai, China.

Methods
Children from grade 1 to 5 in schools for children of migrant workers were randomly chosen for ocular examinations. All children were screened for uncorrected visual acuity and presenting visual acuity. After screening, the children whose uncorrected visual acuity was 20/40 or less received ocular motility evaluation, cycloplegic refraction/non-cycloplegic refraction, and external eye, anterior segment, media, and fundus examinations.

Results
A total of 9673 children were enumerated and 9512 (98.34%) participated in this study. The prevalence of uncorrected, presenting, and best-corrected visual acuity of 20/40 or worse in the better eye were 13.33%, 11.26%, and 0.63%, respectively. The rate of wearing spectacles of the children with visual impairment in one or both eyes was 15.50%. Of these, 26.05% were wearing spectacles with inaccurate prescriptions. Refractive error was a major cause of visual impairment, accounting for 89.48% of all the visual impairment causes. Other causes of visual impairment included amblyopia accounting for 10.12%; congenital cataract, 0.1%; congenital nystagmus, 0.1%; ocular prosthesis, 0.1%; macular degeneration, 0.05%; and opaque cornea, 0.05%.

Conclusions
This is the first study of the prevalence and causes of visual impairment in schools for children of migrant workers in Shanghai, China. The visual impairment rate in schools for children of migrant workers in suburbs of Shanghai in the best eye before vision correction was lower than those of urban children in mainstream schools in Guangzhou in 2012, and higher than students in rural of Beijing in 1998 and in suburb of Chongqing in 2007. The refractive error was the principal cause of the visual impairment of the children of migrant workers. The rate of wearing spectacles was low and the percentage of inaccurate prescriptions, among those who wore spectacles, was high. Uncorrected refractive error was a significant cause of visual impairment in migrant children.

Importance:Uncorrected refractive error causes 90% of poor vision among Chinese children.

Background:Little is known about teachers' influence on children's glasses wear.

Design:Cohort study.

Participants:Children at 138 randomly selected primary schools in Guangdong and Yunnan provinces, China, with uncorrected visual acuity (VA)≤6/12 in either eye correctable to >6/12 in both eyes, and their teachers.

Methods:Teachers and children underwent VA testing and completed questionnaires about spectacles use and attitudes towards children's vision.

Main Outcome Measures:Children's acceptance of free glasses, spectacle purchase and wear.

Results: A total of 882 children (mean age 10.6 years, 45.5% boys) and276 teachers (mean age 37.9 years, 67.8% female) participated. Among teachers,20.4% (56/275) believed glasses worsened children's vision, 68.4% (188/275) felt eye exercises prevented myopia, 55.0% (151/275) thought children with modest myopia should not wear glasses and 93.1% (256/275) encouraged children to obtain glasses.Teacher factors associated with children's glasses-related behaviour included believing glasses harm children's vision (decreased purchase, univariate model: relative risk [RR] 0.65, 95% CI 0.43, 0.98,P< 0.05); supporting children's classroom glasses wear (increased glasses wear, univariate model: RR 2.20, 95% CI 1.23,3.95,P< 0.01); and advising children to obtain glasses (increased free glasses acceptance, multivariate model: RR 2.74, 95% CI 1.29, 5.84,P< 0.01; increased wear, univariate model: RR 2.93, 95% CI 1.45, 5.90,P< 0.01), but not teacher's ownership/wear of glasses.

Conclusions and Relevance:Though teachers had limited knowledge about children's vision, they influenced children's glasses acceptance.