Zhongqiang Zhou

Effect of providing free glasses on children’s educational outcomes in China: cluster randomized controlled trial

Objective To assess the effect of provision of free glasses on academic performance in rural Chinese children with myopia. Design Cluster randomized, investigator masked, controlled trial. Setting 252 primary schools in two prefectures in western China, 2012-13. Participants 3177 of 19 934 children in fourth and fifth grades (mean age 10.5 years) with visual acuity <6/12 in either eye without glasses correctable to >6/12 with glasses. 3052 (96.0%) completed the study. Interventions Children were randomized by school (84 schools per arm) to one of three interventions at the beginning of the school year: prescription for glasses only (control group), vouchers for free glasses at a local facility, or free glasses provided in class. Main outcome measures Spectacle wear at endline examination and end of year score on a specially designed mathematics test, adjusted for baseline score and expressed in standard deviations. Results Among 3177 eligible children, 1036 (32.6%) were randomized to control, 988 (31.1%) to vouchers, and 1153 (36.3%) to free glasses in class. All eligible children would benefit from glasses, but only 15% wore them at baseline. At closeout glasses wear was 41% (observed) and 68% (self reported) in the free glasses group, and 26% (observed) and 37% (self reported) in the controls. Effect on test score was 0.11 SD (95% confidence interval 0.01 to 0.21) when the free glasses group was compared with the control group. The adjusted effect of providing free glasses (0.10, 0.002 to 0.19) was greater than parental education (0.03, −0.04 to 0.09) or family wealth (0.01, −0.06 to 0.08). This difference between groups was significant, but was smaller than the prespecified 0.20 SD difference that the study was powered to detect. Conclusions The provision of free glasses to Chinese children with myopia improves children’s performance on mathematics testing to a statistically significant degree, despite imperfect compliance, although the observed difference between groups was smaller than the study was originally designed to detect. Myopia is common and rarely corrected in this setting. Trial Registration Current Controlled Trials ISRCTN03252665.

Factors Underlying Different Myopia Prevalence between Middle- and Low-income Provinces in China

Currently available data on myopia and spectacle wear are drawn largely from China’s richer and middle-income areas, and little is known about refractive error and spectacle wear in the lowest income provinces. Studies from China and elsewhere suggest that large differences in myopia prevalence may exist between areas of different socioeconomic status within countries, but reasons for these differences are not well understood. The current report details the prevalence and predictors of myopia measured using the identical protocols and equipment in 2 adjoining provinces of western China, middle-income Shaanxi and low-income Gansu. Study methods including institutional review board approvals and consent have been described elsewhere. The study was carried out in Yulin prefecture, Shaanxi, and Tianshui prefecture, Gansu Province, which are nearby areas. Shaanxi’s gross domestic product per capita is

Disordered sleep and myopia risk among Chinese children

US6108 and was ranked 14th among China’s 31 administrative regions in 2012, while Gansu is the second-poorest province in the country (per capita gross domestic product of

Factors influencing the output of rural cataract surgical facilities in China: the SHARP study.

US3100). Yulin is a relatively wealthy region in a middle-income province and Tianshui constitutes a poor region of one of China’s lowest-income provinces. A complete list of primary schools was obtained, and 1 school from each township in the 2 prefectures was selected at random (Yulin, Shaanxi n 1⁄4 132; Tianshui, Gansu n 1⁄4 120). Within each school, 1 class was randomly chosen in each of the 4th and 5th grades. The following data were collected in September 2012: children’s age, sex, boarding at school, parental schooling and migration for work, family wealth, classroom blackboard use, and visual acuity. Children with uncorrected visual acuity of 6/12 in either eye underwent cycloplegic refraction. A study-specific mathematics test was administered as an index of academic achievement. In May and June 2013, we collected data on parental spectacle wear, children’s time spent outdoors and in near/middle distance work using validated instruments. Clinically significant myopia was defined as uncorrected visual acuity of 6/12 in either eye and a spherical equivalent of 0.5 diopter in both eyes. Characteristics were compared between children in the 2 prefectures, accounting for sampling weight and school clustering. Relative risk (RR) estimation using general linear modeling with Poisson regression and robust error variance was used to determine the association between potential risk factors and myopia for the 2 provinces separately and for the total study population. Subjects with missing myopia data (n 1⁄4 306 [1.5%]) were excluded. Among 9489 children in Shaanxi (mean age, 10.4 1.03 years; 53.1% boys), the prevalence of clinically significant myopia (22.9%; 95% CI, 21.2%e24.7%) was nearly twice that of 10 137 children (mean age, 10.7 1.24 years; 49.1% boys) in Gansu (12.7%; 95% CI, 11.3%e14.1%; RR for Shaanxi vs Gansu 1.81 [95% CI, 1.58e2.07; P < 0.001]). Parents out-migrating for work were less common in the Shaanxi cohort (8.10%) than in the Gansu cohort (16.8%; P < 0.001), and families were less likely to be in the lowest wealth tertile for the total sample in Shaanxi (17.2% vs 38.7%; P < 0.001). One-half of our Shaanxi cohort (49%) versus 3.6% in Gansu lived in low population density areas (P < 0.001). Mathematics scores were higher in Shaanxi (P 1⁄4 0.03), and the blackboard was used less in Shaanxi than in Gansu (26.7% of classes spending the majority of classtime directed at the blackboard in Shaanxi vs 45.5% in Gansu; P < 0.001; Table 1, available at www.aaojournal.org). Differences in outdoor activity and near and middle distance work were minimal between Shaanxi and Gansu, and between children with and without myopia (Table 2, available at www.aaojournal.org). Older age (RR, 1.07; 95% CI, 1.02e1.13), parental glasses wear (RR, 1.57; 95% CI, 1.39e1.77), and higher math score (RR, 1.20 [95% CI, 1.13e1.28] per increase of 1 standard deviation in score) were associated with increased risk for myopia in both provinces separately and in the total study population (above RRs are for the total study population). Male sex (RR, 0.81; 95% CI, 0.73e0.91) was associated with lower risk and near work (RR, 1.02 [95% CI, 1.00e1.03] per hour/week increase), with greater risk in the total study population and in Shaanxi alone, but not in Gansu alone. Blackboard use and family wealth were not associated with myopia risk in the multivariate model and no clear linear pattern was found for population density across quartiles (Table 3). Residence in Shaanxi was associated with a 69% increased risk of myopia (RR, 1.69; 95% CI, 1.39; 2.06) after adjusting for other risk factors. The likelihood ratio test (P < 0.001) and pseudo R (<20%) both suggest that the current model fits the data well, and that the conclusion is valid that real, as-yet-unexplained differences exist between myopia prevalence in Shaanxi and Gansu. Even after adjusting for differences in factors associated with myopia, such as near work, school achievement, and outdoor activity, we could not explain much of the large variation in prevalence of clinically significant myopia between middleincome Shaanxi and low-income Gansu. The current study is among the first to compare known myopia risk factors between nearby areas with large differences in myopia rates. It is possible that the low near work demand in the current cohort (8 hours in both Gansu and Shaanxi vs 23e30 hours in Singapore and Australia) might explain the lack of large effects of near work and outdoor activity. Greater blackboard use was protective against myopia in univariate analyses (data not shown), perhaps owing to lower near work demands: weekly near work was lower with highest (6.7 hours) versus lowest (7.6 hours; P < 0.05) blackboard use. Greater blackboard use was also associated with less wealth here (data not shown), because schools in low-income areas could not afford textbooks, which may confound the association with myopia. More research is needed on myopia risk and classroom use of near and distance teaching tools. Our definition of myopia included visual acuity, which limits comparisons with other studies, although not internal comparison between Shaanxi and Gansu. Primary school attendance rates are >95% in the area; thus, this school-based sample is likely representative of the population. It is unlikely that genetic factors

Accuracy of Rural Refractionists in Western China

Purpose Disordered sleep and myopia are increasingly prevalent among Chinese children. Similar pathways may be involved in regulation of both sleep cycles and eye growth. We therefore sought to examine the association between disordered sleep and myopia in this group. Methods Urban primary school children participating in a clinical trial on myopia and outdoor activity underwent automated cycloplegic refraction with subjective refinement. Parents answered questions about childrens sleep duration, sleep disorders (Childrens Sleep Habits Questionnaire [CSHQ]), near work and time spent outdoors. Results Among 1970 children, 1902 (96.5%, mean [standard deviation SD] age 9.80 [0.44] years, 53.1% boys) completed refraction and questionnaires. Myopia < = -0.50 Diopters was present in both eyes of 588 (30.9%) children (1329/3804 = 34.9% of eyes) and 1129 children (59.4%) had abnormal CSHQ scores (> 41). In logistic regression models by eye, odds of myopia < = -0.50D increased with worse CSHQ score (Odds Ratio [OR] 1.01 per point, 95% Confidence Interval [CI] [1.001, 1.02], P = 0.014) and more night-time sleep (OR 1.02, 95% CI [1.01, 1.04, P = 0.002], while male sex (OR 0.82, 95% CI [0.70, 0.95], P = 0.008) and time outdoors (OR = 0.97, 95% CI [0.95, 0.99], P = 0.011) were associated with less myopia. The association between sleep duration and myopia was not significant (p = 0.199) for total (night + midday) sleep. Conclusions Myopia and disordered sleep were both common in this cohort, but we did not find consistent evidence for an association between the two. Trial Registration clinicaltrials.gov NCT00848900

Spectacle design preferences among Chinese primary and secondary students and their parents: A qualitative and quantitative study

PURPOSE To identify factors associated prospectively with increased cataract surgical rate (CSR) in rural Chinese hospitals. METHODS Annual cataract surgical output was obtained at baseline and 24 months later from operating room records at 42 rural, county-level hospitals. Total local CSR (cases/million population/y), and proportion of CSR from hospital and local competitors were calculated from government records. Hospital administrators completed questionnaires providing demographic and professional information, and annual clinic and outreach screening volume. Independent cataract surgeons provided clinical information and videotapes of cases for grading by two masked experts using the Ophthalmology Surgical Competency Assessment Rubric (OSCAR). Uncorrected vision was recorded for 10 consecutive cataract cases at each facility, and 10 randomly-identified patients completed hospital satisfaction questionnaires. Total value of international nongovernmental development organization (INGDO) investment in the previous three years and demographic information on hospital catchment areas were obtained. Main outcome was 2-year percentage change in hospital CSR. RESULTS Among the 42 hospitals (median catchment population 530,000, median hospital CSR 643), 78.6% (33/42) were receiving INGDO support. Median change in hospital CSR (interquartile range) was 33.3% (-6.25%, 72.3%). Predictors of greater increase in CSR included higher INGDO investment (P = 0.02, simple model), reducing patient dissatisfaction (P = 0.03, simple model), and more outreach patient screening (P = 0.002, simple and multiple model). CONCLUSIONS Outreach cataract screening was the strongest predictor of increased surgical output. Government and INGDO investment in screening may be most likely to enhance output of county hospitals, a major goal of Chinas Blindness Prevention Plan.

Self-refraction, ready-made glasses and quality of life among rural myopic Chinese children: a non-inferiority randomized trial

PURPOSE We assessed the prevalence and predictors of inaccurate refractive error among rural refractionists in western China. METHODS A subset of primary school children with visual acuity (VA) ≤6/12 in ≥1 eye, undergoing subjective refinement by local refractionists after cycloplegic autorefraction in an ongoing population-based study, received repeat refraction by university optometrists for quality control. RESULTS Among 502 children (mean age 10.5 years, 53.2% girls), independent predictors of poor (inaccurate by ≥1.0 diopter [D]) refraction by 21 rural practitioners (66.7% with high school or lower education) included hyperopia (odds ratio [OR], 4.2; 95% confidence interval [CI], 2.4-7.3, P < 0.001), astigmatism (OR = 3.8; 95% CI, 2.5-5.6; P < 0.001) and VA uncorrectable to >6/12 by the rural refractionist (OR = 4.7; 95% CI, 3.1-7.3; P = < 0.001). Among 201 children whose vision was uncorrectable in ≥1 eye by the rural refractionists, vision could be improved to >6/12 by the university optometrist in 110 (54.7%). We estimate vision could be so improved in 9.1% of all children refracted by these rural refractionists. A reason for inaccuracy in this setting is the erroneous tendency of rural refractionists to adjust instrument values for accommodation, even under cycloplegia. CONCLUSIONS Rural refractionists in western China have little formal training and frequently fail to optimize VA among children, even when autorefractors are used. Training is needed emphasizing better use of automated refraction, particularly in children with astigmatism and hyperopia.

Pilot study of a novel classroom designed to prevent myopia by increasing children’s exposure to outdoor light

Purpose To identify the specific characteristics making glasses designs, particularly those compatible with adjustable glasses, more or less appealing to Chinese children and their parents. Patients and Methods Primary and secondary school children from urban and rural China with < = −1.00 diopters of bilateral myopia and their parents ranked four conventional-style frames identified by local optical shops as popular versus four child-specific frames compatible with adjustable spectacles. Scores based on the proportion of maximum possible ranking were computed for each style. Selected children and their parents also participated in Focus Groups (FGs) discussing spectacle design preference. Recordings were transcribed and coded by two independents reviewers using NVivo software. Results Among 136 urban primary school children (age range 9–11 years), 290 rural secondary school children (11–17 years) and 16 parents, all adjustable-style frames (scores on 0–100 scale 25.7–62.4) were ranked behind all conventional frames (63.0–87.5). For eight FGs including 12 primary children, 26 secondary children and 16 parents, average kappa values for NVivo coding were 0.81 (students) and 0.70 (parents). All groups agreed that the key changes to make adjustable designs more attractive were altering the round lenses to rectangular or oval shapes and adding curved earpieces for more stable wear. The thick frames of the adjustable designs were considered stylish, and children indicated they would wear them if the lens shape were modified. Conclusions Current adjustable lens designs are unattractive to Chinese children and their parents, though this study identified specific modifications which would make them more appealing.

Safety of spectacles for children's vision: a cluster-randomized controlled trial

To study, for the first time, the effect of wearing ready‐made glasses and glasses with power determined by self‐refraction on childrens quality of life.

An investigation of vision problems and the vision care system in Rural China

We sought to assess light characteristics and user acceptability of a prototype Bright Classroom (BC), designed to prevent children’s myopia by exposing them to light conditions resembling the outdoors. Conditions were measured throughout the school year in the glass-constructed BC, a traditional classroom (TC) and outdoors. Teachers and children completed user questionnaires, and children rated reading comfort at different light intensities. A total of 230 children (mean age 10.2 years, 57.4% boys) and 13 teachers (36.8 years, 15.4% men) completed questionnaires. The median (Inter Quartile Range) light intensity in the BC (2,540 [1,330–4,060] lux) was greater than the TC (477 [245–738] lux, P < 0.001), though less than outdoors (19,500 [8,960–36,000] lux, P < 0.001). A prominent spectral peak at 490–560 nm was present in the BC and outdoors, but less so in the TC. Teachers and children gave higher overall ratings to the BC than TC, and light intensity in the BC in summer and on sunny days (>5,000 lux) was at the upper limit of children’s comfort for reading. In summary, light intensity in the BC exceeds TC, and is at the practical upper limit for routine use. Children and teachers prefer the BC.