Does Performing the Chinese Eye Exercises Help Protect Children’s Vision? – New Evidence from Primary Schools in Rural Northwestern China

References

• National Health Commission of the People’s Republic of China. China will carry out more-targeted myopia intervention. Available from: http://www.nhc.gov.cn/xcs/s7847/201905/11c679a40eb3494cade977f65f1c3740.shtml. Accessed 508, 2019 (In Chinese)
   Google Scholar
• Ma X, Zhou Z, Yi H, et al. Effect of providing free glasses on children’s educational outcomes in china: cluster randomized controlled trial. BMJ. 2014;349:g5740. doi:10.1136/bmj.g574025249453
   PubMed Web of Science ®Google Scholar
• Glewwe P, Park A, Zhao M. A better vision for development: eyeglasses and academic performance in rural primary schools in China. J Dev Econ. 2016;122(C):170–182. doi:10.1016/j.jdeveco.2016.05.007
   Web of Science ®Google Scholar
• Zhao J, Pan X, Sui R, et al. Refractive error study in children: results from Shunyi District, China. Am J Ophthalmol. 2000;129:427–435. PMID: 10764849. doi:10.1016/S0002-9394(99)00452-310764849
   PubMed Web of Science ®Google Scholar
• He M, Zheng Y, Xiang F. Prevalence of myopia in urban and rural children in mainland China. Optom Vis Sci. 2009;86:40–44. doi:10.1097/OPX.0b013e318194071919104465
   PubMed Web of Science ®Google Scholar
• Li Y, Liu J, Qi P. The increasing prevalence of myopia in junior high school students in the Haidian District of Beijing, China: a 10-year population-based survey. BMC Ophthalmol. 2017;17(1):88. doi:10.1186/s12886-017-0483-628606071
   PubMed Web of Science ®Google Scholar
• Chen M, Wu A, Zhang L, et al. The increasing prevalence of myopia and high myopia among high school students in Fenghua city, eastern China: a 15-year population-based survey. BMC Ophthalmol. 2018;18:159. doi:10.1186/s12886-018-0829-829970057
   PubMed Web of Science ®Google Scholar
• Ostberg O, Horie Y, Feng Y. On the merits of ancient Chinese eye acupressure practices. Appl Ergon. 1992;23:343–348. PMID: 15676881. doi:10.1016/0003-6870(92)90296-815676881
   PubMed Web of Science ®Google Scholar
• Zhao R, He X, Zhu J. Analysis on the evolution of students’ eye exercises. Shanghai J Prev Med. 2009;21(05):214–217. (In Chinese).
   Google Scholar
• Han X, Miao HL, Huang D. Investigation of junior school student myopia in high-altitude Tibetan areas in Qinghai Province. Int Eye Sci. 2014;14:913–915.
   Google Scholar
• Kang MT, Li SM, Peng X, et al. Chinese eye exercises and myopia development in school age children: a nested case-control study. Sci Rep. 2016;6(1):1–8.28442746
   PubMed Web of Science ®Google Scholar
• Wang L, Du M, Yi H, et al. Prevalence of and factors associated with myopia in Inner Mongolia medical students in China, a cross-sectional study. BMC Ophthalmol. 2017;17(1):52. doi:10.1186/s12886-017-0446-y28438126
   PubMed Web of Science ®Google Scholar
• Yi H, Zhang L, Ma X, et al. Poor vision among China’s rural primary school students: prevalence, correlates and consequences. China Econ Rev. 2016;33:247–262. doi:10.1016/j.chieco.2015.01.004
   Web of Science ®Google Scholar
• Lin Z, Vasudevan B, Jhanji V, et al. Eye exercises of acupoints: their impact on refractive error and visual symptoms in Chinese urban children. BMC Complement Altern Med. 2013;13(1):306. doi:10.1186/1472-6882-13-30624195652
   PubMed Web of Science ®Google Scholar
• Lin Z, Vasudevan B, Fang SJ, et al. Eye exercises of acupoints: their impact on myopia and visual symptoms in Chinese rural children. BMC Complement Altern Med. 2016;16(1):349. doi:10.1186/s12906-016-1289-427599547
   PubMed Web of Science ®Google Scholar
• Wang H, Qian Y, Congdon N, Boswell M, Rozelle S, Ma X. Effect of Chinese eye exercises on change in visual acuity and eyeglasses wear among school-aged children in rural China: A propensity-score-matched cohort study. BMC Complement Altern Med. 2020;20(1):82. doi:10.1186/s12906-020-2878-9
   Web of Science ®Google Scholar
• Li S-M, Kang M-T, Peng -X-X, et al. Efficacy of Chinese eye exercises on reducing accommodative lag in school-aged children: A randomized controlled trial. PLoS One. 2015;10(3):e0117552. doi:10.1371/journal.pone.011755225742161
   PubMed Web of Science ®Google Scholar
• Xiong R, Liu Q. Investigation of incorrect performance of students’ eye exercises. Chin J School Health. 2001;22(06):566 (In Chinese).
   Google Scholar
• Zhao R, He X, Zhu J, Lu L, Zhang S. An analysis of beliefs and behaviors related to Chinese eye exercises among primary and secondary school teachers and students in Shanghai. Chin J School Health. 2012;33(03):270–272. (In Chinese).
   Google Scholar
• Li M, Ren Z. The necessity of reforming Chinese eye exercises. Chin J School Health. 2003;24(05):547–548. (In Chinese).
   Google Scholar
• Ministry of Education. Notice on distributing Comprehensive plan to prevent myopia among school-age children. Available from: http://www.moe.gov.cn/srcsite/A17/moe_943/s3285/201808/t20180830_346672.html. Accessed 515, 2020 (In Chinese)
   Google Scholar
• Greene W. Econometric Analysis. 8th ed. London: Pearson Education; 2018.
   Google Scholar
• Greenland S. An introduction to instrumental variables for epidemiologists. Int J Epidemiol. 2000;29(4):722–729. doi:10.1093/ije/29.4.72210922351
   PubMed Web of Science ®Google Scholar
• Hernán MA, Robins JM. Instruments for causal inference: an epidemiologist’s dream? Epidemiology. 2006;17(4):360–372. doi:10.1097/01.ede.0000222409.00878.3716755261
   PubMed Web of Science ®Google Scholar
• Martens EP, Pestman WR, de Boer A, Belitser SV, Klungel OH. Instrumental variables: applications and limitations. Epidemiology. 2006;17(3):260–267. doi:10.1097/01.ede.0000215160.88317.cb16617274
   PubMed Web of Science ®Google Scholar
• Baiocchi M, Cheng J, Small DS. Instrumental variable methods for causal inference. Stat Med. 2014;33(13):2297–2340. doi:10.1002/sim.612824599889
   PubMed Web of Science ®Google Scholar
• Ertefaie A, Small DS, Flory JH, Hennessy S. A tutorial on the use of instrumental variables in pharmacoepidemiology. Pharmacoepidemiol Drug Saf. 2017;26(4):357–367. doi:10.1002/pds.415828239929
   PubMed Web of Science ®Google Scholar
• Lousdal ML. An introduction to instrumental variable assumptions, validation and estimation. Emerg Themes Epidemiol. 2018;15(1):1–7. doi:10.1186/s12982-018-0069-729387137
   PubMed Web of Science ®Google Scholar
• Moss HA, Melamed A, Wright JD. Measuring cause-and-effect relationships without randomized clinical trials: quasi-experimental methods for gynecologic oncology research. Gynecol Oncol. 2019;152(3):533–539.30876500
   PubMed Web of Science ®Google Scholar
• Maciejewski ML, Brookhart MA. Using instrumental variables to address bias from unobserved confounders. JAMA. 2019;321(21):2124–2125. doi:10.1001/jama.2019.564631046064
   PubMed Web of Science ®Google Scholar
• National Bureau of Statistics of China. China Statistical Yearbook. Beijing: China Statistics Press; 2013 (In Chinese).
   Google Scholar
• Camparini M, Cassinari P, Ferrigno L, et al. ETDRS-Fast: implementing psychophysical adaptive methods to standardized visual acuity measurement with ETDRS charts. Invest Ophthalmol Vis Sci. 2001;42(6):1226–1231.11328731
   PubMed Web of Science ®Google Scholar
• Tong L, Saw SM, Tan D, et al. Sensitivity and specificity of visual acuity screening for refractive errors in school children. Optom Vis Sci. 2002;79(10):650–657. doi:10.1097/00006324-200210000-0001112395920
   PubMed Web of Science ®Google Scholar
• He M, Zeng J, Liu Y, Xu J, Pokharel GP, Ellwein LB. Refractive error and visual impairment in urban children in southern China. Invest Ophthalmol Vis Sci. 2004;45(3):793–799. doi:10.1167/iovs.03-105114985292
   PubMed Web of Science ®Google Scholar
• Luo H-D. Defining myopia using refractive error and uncorrected logMAR visual acuity >0.3 from 1334 Singapore school children ages 7–9 years. Br J Ophthalmol. 2006;90(3):362–366. doi:10.1136/bjo.2005.07965716488963
   PubMed Web of Science ®Google Scholar
• Flitcroft DI, He M, Jonas JB, et al. IMI - defining and classifying myopia: a proposed set of standards for clinical and epidemiologic studies. Invest Ophthalmol Vis Sci. 2019;60(3):M20–M30. doi:10.1167/iovs.18-2595730817826
   PubMed Web of Science ®Google Scholar
• National Bureau of Statistics of China. China Rural Household Survey Yearbook. Beijing: China Statistics Press; 2013 (In Chinese).
   Google Scholar
• Chen Q. Relaxed population policy, family size and parental investments in children’s education in rural Northwestern China. Int J Educ Dev. 2017;54(C):39–50. doi:10.1016/j.ijedudev.2017.03.009
   Web of Science ®Google Scholar
• White H. A heteroskedasticity-consistent covariance matrix estimator and a direct test for heteroskedasticity. Econometrica. 1980;48(4):817–838. doi:10.2307/1912934
   Web of Science ®Google Scholar
• Maddala GS. Limited-Dependent and Qualitative Variables in Econometrics. Cambridge: Cambridge University Press; 1983:123.
   Google Scholar
• Bound J, Jaeger DA, Baker R. Problems with instrumental variables estimation when the correlation between the instrument and the endogenous explanatory variable is weak. J Am Stat Assoc. 1995;90:443–450.
   Web of Science ®Google Scholar
• Staiger D, Stock JH. Instrumental variables regression with weak instruments. Econometrica. 1997;65:557–586. doi:10.2307/2171753
   Web of Science ®Google Scholar