In July 2021, China announced new regulations for private tutoring companies, an industry worth over $120 billion, obliging them to operate on a not-for-profit basis and limiting their operating hours. Share prices tumbled on the Shanghai and Hong Kong stock exchanges, and the western financial press speculated about what was going on.1 But from a public health perspective, these measures were clearly, at least in part, a response to continuing concerns about the way in which the expansion of education has precipitated an epidemic of myopia and high myopia in China, and elsewhere in East and Southeast Asia.
While these initiatives are part of broader policy issues, driven by concerns about a low birth rate, we will focus on how these policy changes support attempts to deal with the myopia epidemic. We will outline the problems posed by the epidemic of myopia and the approaches now available to address these problems, and put the new policy developments in China into this context. We will use the term “myopia prevention” to cover measures aimed at reducing the prevalence of myopia, and “myopia control” to cover those aimed at reducing the progression of myopia to high myopia. Since the epidemic of myopia has affected most parts of East Asia, and at least Singapore in Southeast Asia,2 and since some projections suggest that most of the world will be affected by increases in prevalence by the year 2050,3 what is happening in China has implications for the rest of the Asia-Pacific region, and indeed the whole world.
WHAT IS THE MYOPIA PROBLEM?
The Epidemic of Myopia in East and Southeast Asia
Yusufu et al have provided a broad overview of eye diseases in the Asia-Pacific region.4 There is now indisputable evidence of an epidemic of myopia and high myopia in parts of East and Southeast Asia, including mainland China, Hong Kong and Macau, Chinese Taipei (commonly called Taiwan), South Korea, Japan, and Singapore. In these locations, around 80% of students completing secondary schooling are myopic and need correction, while 10% to 20% of them are highly myopic,2,5,6 and are thus at high risk of developing potentially blinding pathological myopia.
A Cautionary Note—the Importance of Cycloplegia
Cycloplegia is the gold standard for the detection of myopia in children, adolescents, and younger adults,7 but published papers, from China and elsewhere, use a variety of methods for detecting myopia, with most using some variation on noncycloplegic refraction (NCR). China's National Health Commission now specifies NCR for school screening.8 This approach is fit-for-purpose as a screening tool because it identifies all children with myopia, but with some over-referral. In the Shandong Children Eye Study, while 16.4% of 4- to 6-year-olds were identified as myopic with NCR, only 2.2% were actually myopic after cycloplegia.9,10 This balance changes progressively as the age-specific prevalence of myopia rises, so that in 16- to 18-year-olds nearly 90% were correctly identified as myopic (Fig. 1). The need for cycloplegia in senior school students and young adults has been confirmed by results from the Anyang University Student Eye Study.11 The distinction between myopia and pseudomyopia (those who are classified as myopic before cycloplegia, but not after) is important because children with myopia need optical correction, while those with pseudo-myopia do not, unless they have other problems.
;)
Figure 1: Prevalence of myopia under cycloplegic and noncycloplegic conditions (data replotted from reference 10). Data for this study was collected in urban and rural areas from Shandong Province in north-eastern China.
After referral, children will then generally receive a cycloplegic refraction before a subjective prescription. The recently published NCR methodology for a low-cost “Child and Adolescent Myopia Survey” (CAMS) may provide a model for future expansion of screening in China.12 NCR can also be used for surveillance of trends, since the errors inherent in NCR are likely to be similar over time for children of a given age. But the limitations of NCR data, namely overestimation of myopia, particularly in younger children, need to be understood. Using these national data for more detailed scientific analysis poses particular problems, for example, it is obvious that a study of risk factors for myopia in 4- to 6-year-olds, where only 10% of those identified as myopes are actually myopic, would be essentially meaningless.
Some Important Features of the Epidemic
Data from the Shandong Children Eye Study (Fig. 2)9 also shows a typical picture of the development of myopia in areas with a high prevalence of myopia. The prevalence of myopia starts to increase from the age of about 6, when children start school in China. The rate of increase is slow in the early primary school years, but it accelerates, and by the end of primary school, over 50% of children are already myopic. The increase in prevalence then progressively slows through later years of education.
Figure 2: Prevalence of myopia and high myopia by age (data replotted from reference 9). Data for this study was collected in urban and rural areas from Shandong Province in north-eastern China.
As the epidemic has developed, the age of onset of myopia has become younger, as is illustrated by the sequential studies from Taiwan.13 In Singapore,14 Taiwan,15 and Hong Kong,16 the prevalence of myopia in preschool and Grade 1 students is well over 10%, even with cycloplegia, but this is not yet the case in mainland China, when cycloplegia is used.9,17–20 Further analysis of this difference may provide important insights into causal factors.
For high myopia,9 the prevalence remains close to or under 1% up to the age of 11 to 12 years (Fig. 2), but it continues to increase at least until the end of schooling. This pattern suggests that the myopia that develops during the early primary years progresses to the cutoff for myopia of −6D within 5 or 6 years of starting school.21 Age-specific progression rates in the region are generally consistent with this timing.22,23 The epidemics of myopia and high myopia are thus inextricably linked.
The Importance of High and Pathological Myopia
High myopia is not just a refractive problem requiring correction. It can develop into pathological myopia later in life, leading to uncorrectable visual impairment and blindness. Ohno-Matsui and colleagues have recently reviewed this area in detail.24 Pathological myopia is defined by typical complications in the fundus (posterior staphyloma or myopic maculopathy equal to or more serious than diffuse choroidal atrophy). More unusual lesions such as dome-shaped macula and myopic traction maculopathy are sometimes observed. This poses a major challenge to countries, including China, in which the prevalence of high myopia is high in younger cohorts, since pathological myopia and the associated loss of vision tends to affect the most educated at the peak of their working life. It is now a major cause of visual impairment and blindness in much of the region.25–27 However, so far, China has not defined targets for control of high myopia.
The Challenges of Myopia Prevention and Control
The characteristic features of the epidemic of myopia, therefore, define 3 key challenges:
- Providing adequate correction for myopic children as they develop. This means developing effective school screening and prompt referral for optical correction and myopia control.
- Reducing the prevalence of myopia.
- Slowing the progression of myopia to limit the development of high and ultimately pathological myopia.
INCREASED UNDERSTANDING OF THE RISK FACTORS FOR MYOPIA—THE KEY TO MYOPIA PREVENTION
Two major causal and modifiable risk factors for myopia have been identified.28
Educational Pressures
There is little myopia in children who get little or no schooling, but as school systems develop and more children get more education, the prevalence of myopia after 12 years of schooling increases to around 20%—a figure seen in typical western school systems. Within a school system, children who receive more years of schooling tend to be more myopic, and, at a given level of schooling, higher-achieving children tend to be more myopic, as do children following more academic streams or classes.2 A causal role for education has been confirmed with Mendelian randomization analysis29,30 and regression-discontinuity analysis,31 but a randomized clinical trial (RCT) would be unethical in this area. The increase in the prevalence of myopia during schooling is primarily due to increased exposure to environmental risk factors experienced as a school student, rather than increasing age.32
There are a number of factors that may be distal drivers of the epidemic, in particular policies that impose high exposure to risk factors for myopia on school children. School systems in the “high prevalence of myopia” countries generally involve competition to enter academically-oriented streams that begin in the early years of schooling.33 Homework loads are generally higher and extensive use is made of private tutoring. School days are crowded and long, leaving little time for outdoor activities. Unfortunately, there has been no significant work to establish if changing these exposures results in effective prevention, although the widespread policy changes to reduce such childhood exposures in China will provide many opportunities to conduct “natural experiments,” which would make a valuable contribution to knowledge in this area.
Time Outdoors
Children who spend more time outdoors are protected from the onset of myopia.18,34–37 The postulated mechanism (increased retinal dopamine release due to brighter light outdoors, with dopamine slowing the rate of axial elongation,35) has been confirmed in studies of experimental myopia in animals.38–41 There is some evidence that it also applies to humans.42 The ability of increased time outdoors to slow the onset of myopia has been demonstrated in RCTs18,43,44 and in system-wide implementation.45 Whether it also affects myopia progression is currently controversial.
The importance of light exposures during time outdoors has revived interest in lighting conditions in schoolrooms.46 One paper from China has reported major preventive effects of increasing light intensities in classrooms,47 and one of the papers in this special issue reports on the deleterious effects of low light intensities in kindergarten classrooms.48 If confirmed, these observations offer some simple interventions to control myopia, ranging from a prototype bright classroom,49 to systematic upgrades of schoolroom lighting. Light intensity may not be the only important parameter, and a recent paper has reported that repeated exposure to low-level red-light in a clinical situation also has the ability to prevent the progression of myopia.50 Further experimentation with lighting conditions is therefore warranted.
Has Increased Use of Digital Devices Played a Role?
A common question is whether the use of digital devices has created the epidemic of myopia. However, the World Wide Web only became available for public use in 1993, and tablet computers and smartphones were not available until 2008 to 2010. Since the prevalence of myopia was already high for young adults in the 1980 s in Taiwan, Hong Kong, and Singapore, and by the 1990 s in mainland China,2,5 these devices cannot have played a major role in the onset of the epidemic. While smartphones have since become ubiquitous in much of the world, the first students to have had access to these devices for their entire lives will not finish school until around 2027.
The crucial question, therefore, is whether digital devices have played a role in recent increases in prevalence. The present evidence is somewhat contradictory. Data from Hong Kong suggest that there has been little increase in the prevalence of myopia that could be associated with increased use of digital devices over the past 20 years.16 In contrast, data from Taiwan has documented recent increases in prevalence that could plausibly be attributed to the uptake of digital devices.15 It may, in fact, be more productive to look for associations of digital device use with increases in myopia prevalence in locations where the baseline prevalence of myopia is lower.
In 2019, Dirani et al51 postulated that digital screen time might have become the sole modifiable risk factor for myopia, responsible for an increased near workload and for decreased time spent outdoors. Two recent systematic reviews and meta-analyses have addressed this issue. The first concluded that there was no clear pattern of association.52 A more recent meta-analysis53 cautiously concluded that screen time might be associated with myopia, but noted that none of the studies used reliable methods for measuring device use. Clearly, further research is required.
If future research does establish a clear causal link, it seems possible that limiting device use could simply lead children to revert to previous patterns of behavior, which had already made them myopic. In addition, if the established pattern of spending more time indoors persists, it may be necessary to take active steps to encourage children to get outside. Without additional measures, limiting use of digital devices could therefore have little impact on myopia, although it may have other social benefits.
Developments in the Control of Myopia Progression
There are now several techniques for clinically controlling the progression of myopia.54,55 Optical approaches to control of progression now include orthokeratology,56 and spectacle and contact lens designs that impose myopic defocus.57–59 The only pharmacological approach that has become part of clinical practice is the use of atropine, particularly at low doses.60,61 All of these approaches seem to be capable of reducing progression by at least 50% over several years. Current clinical methods can therefore address the need to control myopia progression, leading to control of high myopia, and implementation is now the key challenge.
THE DEVELOPMENT OF MYOPIA PREVENTION AND CONTROL IN EAST AND SOUTHEAST ASIA
Attempts to control myopia in the region have had a long history. Taiwan started to take action on myopia from around 1983, with epidemiological studies funded by the military.62 In schools, school nurses began to test all school students for reduced visual acuity and referral for clinical treatment, with the widespread use of atropine.63 A number of interventions were recommended to prevent and control myopia. But in 2010, with the increasing evidence for a protective effect of time outdoors, Taiwan dropped some of these, and incorporated the aim of 2 hours outdoors per day into its school-based myopia prevention strategy, with positive effects.45
Interest in myopia also emerged in Singapore in 1988, with a paper on the rising prevalence of reduced uncorrected visual acuity in younger adults in Singapore.64 This raised labor market concerns, leading to a long tradition of myopia research in Singapore, including a study on the use of atropine for the control of the progression of myopia that popularized the use of low-dose atropine.60 Singapore introduced an emphasis on increasing time outdoors in 2008, again with positive effects.65
Mainland China started to react to the problem even earlier. In 1963, in response to early signs of an increasing prevalence of myopia in the senior high school years, a program of eye exercises was developed, based on Traditional Chinese Medicine. Since then, Chinese students in primary (age 6 to 12 years) and junior high schools (age 12 to 15 years) have performed eye exercises twice a day at school, but the prevalence of myopia has continued to increase. School-based eye exercises have clearly not been able to prevent the epidemic.66,67
The approaches in Taiwan and Singapore have differed significantly. In Singapore, the emphasis has been on parental responsibility. In Taiwan, there has been more active promotion of time outdoors in schools through the Tian-Tian 120 program, with greater evidence of success. The success of these national implementation plans was groundbreaking, in that the results provided proof of principle that increased time outdoors could prevent the onset of myopia in real life. However, it is also important to note that the results fell well short of restoring the lower myopia prevalence seen before the expansion of schooling. Notably, in both locations, there has been little attempt to fundamentally change what happens in schools, and the effectiveness of the interventions may therefore be constrained.
China's approach is essentially school-based and, as will be discussed later, involves extensive changes to school and ancillary programs, that may facilitate increasing the amount of outdoor time. In contrast, in other parts of the region, such as Japan and South Korea, little official attention has been devoted to monitoring or preventing myopia.
SHADOW EDUCATION—A GENERAL PROBLEM IN THE “HIGH PREVALENCE OF MYOPIA” COUNTRIES
The important role played by private tutoring companies, an industry is often known as shadow education, in East and Southeast Asian countries has been recognized by education experts for a number of years.68 It has raised particular concerns on both educational grounds, since it reinforces rote-learning and an examination-oriented competitive culture within schooling, and on social equity grounds, since the greater parental capacity to pay for private tutoring may further advantage children already advantaged by family educational background. An epidemiological link of additional tutoring to the development of myopia has been documented.33,69,70
Despite this wide recognition, there has been little attempt to control the sector, with 2 exceptions. While there has been no focus on myopia, South Korea has tried to limit private tutoring since the 1980 s on equity grounds, but with little success.71 In fact, in the year 2000 attempts to limit it were declared unconstitutional.72 It is now estimated that over 75% of school children receive some private tutoring, for nearly 7 hours a week.73 It was estimated to cost parents the equivalent of 2.57% of South Korea's gross domestic product (GDP) in 2006,71 exceeding the government's education budget and accounting for nearly 20% of household income.74 In 2016, there were 73,000 registered private tutoring schools in South Korea, with over half in the capital Seoul.75 This may help explain the exceptionally high prevalence of myopia (with cycloplegia, 96.5% myopia; 21.6% high myopia) reported for 19-year-old males in Seoul.76
Japan has also tried to reform its education system, over general concerns about student health and behavior, rather than concerns about myopia. In the 1990s Japan reduced school hours, under the Yutori (relaxed) school reforms.77 A recent paper showed that the constant increase in myopia and high myopia in medical students at Asahikawa Medical University was halted for students educated under the new regime,78 but to our knowledge, there is no other information on the impact of these measures on myopia. Despite these reforms, Japan has consistently remained a high performer in the triennial PISA surveys [PISA, a Program for International Student Assessment run by the Organization for Economic Cooperation and Development (OECD)].79,80 In general, the conclusion has been that competition and reliance on private tutoring have not changed significantly, despite the reforms. A recent small survey that used NCR has reported that the prevalence of myopia in junior high schools is as high as 94.9%.81 Clearly a larger survey using cycloplegic refraction is required.
RECENT DEVELOPMENTS IN CHINA
From the year 2000, several sound epidemiological studies using cycloplegia had shown that the prevalence of myopia in at least some parts of China was very high, reaching 80% plus in urban senior high schools.9,82,83 There was undoubtedly a problem. In 2012, Professor Ling Li, a health economist at the National Center for Economic Development in Beijing, produced a National Vision Care Report. It was circulated in Chinese in 2015, but only a brief author's summary of the report is available in English.84
This report recognized that China was faced with 2 problems—an aging population suffering from near vision impairment due to presbyopia, and the emergence of an epidemic of myopia in the younger generations. The report, therefore, focused on the need to ensure good access to refractive services, which were relatively poorly developed in China. The problem of the increasing levels of high myopia was mentioned, but was not a central focus. The report recommended development of an independent profession of optometry, which could ultimately deliver the network of local refractive services that are common in developed countries outside of China. Professor Li argued that China needed to transition from guaranteeing the right to see, to a new phase in which the challenge was to ensure that the whole population could see well throughout their lifetime. This seems to foreshadow a situation in which citizens will have a guaranteed right to achieve their best-corrected visual acuity, covered by medical insurance.
A key part of the report was an analysis of the economic costs of uncorrected myopia and presbyopia to China. The report estimated that the cost of lost productivity was over 1% of China's GDP, while the costs in terms of disability-adjusted life years amounted to nearly 2%. Costs of this level attract the attention of governments, particularly since failure to act could affect labor supply, with economic and national security implications. Overall, the report recommended the development of an integrated national vision care initiative, including coverage of corrections by health insurance.
These recommendations were picked up to some extent in the 13th National Plan of Eye Health, also released in 2016.85 Among its objectives were the need to focus on treatment and correction of uncorrected refractive errors and associated visual impairment in children. Every county was to have qualified optometrists to provide optical services. In China, a country is the third level of administration in China, with 2852 county-level divisions as of 2015. On average, a country, therefore, serves approximately half a million people, but counties vary a lot in size. This goal has stimulated the training of optometrists in China, but meeting the goal is probably still a work in progress. The Plan also proposed vision screening for children aged 0 to 6 years, as well as for elderly people. This would help address the issue of presbyopia, but has only limited relevance to myopia, since most myopia develops after the age of 6.
In 2018, China's President Xi Jinping again drew attention to the major impact of myopia on the health of China's children.86 This was followed by a document entitled “Notice of Ministry of Education and 8 Other Departments on Issuing the Implementation Plan of Comprehensive Control of Myopia in Children and Adolescents.”87 This plan specified goals of reducing the prevalence of myopia by at least 0.5% annually from the 2018 baseline prevalence by 2023. In provinces with high prevalence, the goal was an annual decrease of at least 1%. By 2030, the prevalence of myopia was to be controlled at 3% in children aged 6 years old, to less than 38% in primary school students, to less than 60% in middle school students, and to less than 70% in high school students. These were rather modest goals, relative to the challenges, and success in meeting them would still leave China with a major problem, but are of a similar magnitude to those achieved in Singapore and Taiwan. The document also stated that early onset and rapid progression to high myopia had become a substantial problem, but there was no specific target set.
For parents, recommendations to increase time outdoors and physical exercise and to lighten extracurricular study burdens were particularly important, given their evidence base. For schools, there were similar recommendations on reducing academic pressure, with limits on homework and examinations, particularly in the early years. The importance of life and games for children aged 3 to 6 years, were recognized, with at least 2 hours outdoors each day, including at least 1 hour of physical activity.
This was followed in mid-2021 by a document from the State Council on new initiatives known formally as “Opinions on Further Reducing the Burden of Student's Homework and Off-campus Training in Compulsory Education,”88 and commonly known as the “Double Reductions” policy. One key paragraph defines the goals and timelines clearly:
“Students’ overwork burdens and off-campus training burdens, family education expenditures, and parents’ corresponding energy burdens will be effectively reduced within 1 year, with significant changes within 3 years ……” (unofficial translation)
This goal addresses some issues that might otherwise weaken ongoing myopia prevention and control initiatives. It was always likely that some, prioritizing academic success, would seek to compensate for homework limitations by increasing the use of private tutorial companies.89 The 2018 National Plan included some advice to parents:
“Lighten extracurricular studying burdens. Coordinate with the school to lighten the studying burdens effectively. Do not enroll children in afterschool training or extracurricular studying sessions blindly. Choose extracurricular studying sessions reasonably according to children's interests. Avoid burden reduction at school but increases at home.” (unofficial translation)
The new measures make it more difficult to get around the intent of the new policies. It is clear that many details of the new approach are still to be filled in, but there is a consistent thread around reducing the burden on students to improve several aspects of student health, including myopia, obesity, and mental health. A reasonable interpretation is that the latest changes, which have been combined with significant limitations placed on the emerging private school sector, signal a determination on the part of the Chinese government to produce fundamental change in China's examination-dominated school system, postponing intensive educational pressures until the more senior years. From the perspective of myopia control, this makes good sense. Other countries with a high prevalence of myopia need to watch these developments closely because these initiatives have a good chance of making a substantial difference to the lives of school children in China, and to the prevalence of myopia and high myopia.
CHALLENGES FOR THE FUTURE
We now have several effective methods for the control of myopia progression, and hence for control of high myopia and the subsequent development of pathological myopia. These are ready for systematic use in clinical practice. Particularly in countries with a high prevalence of myopia, such as China, referral for correction and progression control needs to be facilitated by systematic school screening and referral for correction and control of progression. There is now a promising model in the CAMS survey.12 Systematic use of this approach should enable the epidemic of high myopia to be brought under control, so implementation has to be a priority.
The situation is more problematic for reducing the overall prevalence of myopia. Here, limited but significant success has been achieved by increasing the amount of time that children spend outdoors. While the evidence suggests that further increasing time spent outdoors should lead to greater protection, it is quite widely feared that this may reduce educational outcomes. The solution, from the perspective of myopia, may come from maximizing changes in the early school years, opening up more opportunities for increased time outdoors for both play and learning, while minimizing changes in the later school years. However, other health considerations around obesity and mental health may require significant changes in the more senior school years as well.
There are many opportunities and challenges in these new developments for Chinese ophthalmologists and optometrists. There is clearly a need to ensure that all new policies are firmly based on scientific evidence. Some may require fine-tuning. For example, in Chinese schools, there is supposed to be a 10-minute break between classes, but much of this time has been absorbed into teaching time, with tight controls over the ability of students to leave the classroom or school buildings, and even to make noise. A recent directive from the Ministry of Education stresses that the 10-minute breaks must be respected, with students given greater freedom during this time.90 If these breaks were consolidated into fewer but longer breaks, it would make it easier for students to get outdoors, thereby contributing to myopia prevention. Public schools will also offer after-school programs, 5 days a week from the end of school to a pick-up time matched to the normal working hours of parents, and will have school holiday programs as well. While the existing programs of this kind tend to concentrate on homework supervision, these new initiatives will provide significant opportunities for students to get more time outdoors.
There is an equally important need to provide professional development to the clinical, public health and education communities, and to educate the general public because myopia is an area in which understandings have changed very markedly over the past 20 years. And, most of all, there is an urgent need to monitor the impact of the changes. The Double Reductions policy states that 9 major cities have been identified as national pilots, and at least 1 prefecture and city shall be selected for pilots in other provinces. This is a pragmatic research-based approach to determining what works in achieving the aims.
Partnerships with education researchers are also vital. There is some concern that changes to school practices may undermine the high educational outcomes that China has achieved in the PISA international surveys. But it is equally possible that school reform, particularly in the early years, may be the key to comprehensive myopic control, without compromising outcomes. For example, a study in this special issue documents a lower prevalence of myopia in local students studying in an international school in Hong Kong than in local students studying in local schools, although the parental risk factors for myopia point in the other direction.91 The international school follows the International Baccalaureate, and thus academic standards are very high, which shows that the prevalence of myopia in Chinese populations can be much lower than it currently is, even in a high-quality educational environment. It is not clear if it is what the school does, or what this selected group of parents does in terms of lifestyle, that makes the difference, but the size of the effect means that it is worth establishing what the important factors are. The CAMS survey also documented significantly lower myopia prevalence rates in Sports and Martial Arts schools, but it is not clear to us how high their academic standards are.
CAMS also documented a slightly higher prevalence of myopia in key schools,12 consistent with the evidence outlined above. But the role of the key school system in China needs particular scrutiny because key schools seem to play a major role in creating intense competition for places, ultimately affecting most parts of the education system. As a result, reform in this area may be crucial.
Considerable evidence suggests that there may actually be educational benefits from reduced educational pressure on students in the preschool and early primary school years. There is, for example, an extensive educational literature on the positive benefits of a more self-directed and problem-solving approach to learning, rather than simply learning the answers.92 Self-directed learning has also been shown to promote the development of executive functioning, namely the ability to make rational decisions about one's own behavior,93 which may be relevant to concerns about gaming disorder, which has now been classified as a mental health condition in the 11th Revision of the International Classification of Diseases. The OECD has an active research program in Innovative Learning Environments.94
China is starting to move in this direction, with a clear focus on student health and welfare, reducing the burden on students in parallel with reducing the burden on parents, changing the school system internally and restructuring the entire educational environment. We can expect to see many more innovations as China rolls out its myopia prevention and control plan and its educational reform plan. Our colleagues in China have the challenge of providing the critical evidence on success in meeting the goals of myopia prevention and control, and the impacts, whatever they may be, on educational outcomes.
Despite the disruptions caused by the COVID pandemic, it seems certain that more and more countries will pursue the development of their education systems, as part of their economic development strategy. This direction is encouraged by the United Nations Sustainable Development Goals (SDGs), especially Goal 4, which aims to “ensure inclusive and equitable quality education and promote lifelong learning opportunities for all.”95 This goal is supported by a range of international programs run by UNESCO and UNICEF, and other international institutions, such as the World Bank and the OECD. The United Nations General Assembly has also recently passed a resolution on Vision for Everyone—accelerating action to achieve the SDGs, which commits members “to make eye care an integral part of universal health coverage,” as a vital part of making progress on the entire range of SDGs.96 Provided that other countries learn the lessons from China's, and more broadly the East and Southeast Asian experience of an epidemic of myopia and high myopia, then it should be possible to achieve these development goals without compromising the eye health of future generations.
Acknowledgements
Catherine Jan is supported by a postgraduate scholarship thanks to the contribution of the Australian Commonwealth Government.
REFERENCES
1. Wall Street Journal. Wall Street Gets a Chinese Education. Published on July 27, 2021. Available at
https://www.wsj.com/articles/china-restrictions-private-tutoring-market-xi-jinping-11627409426. Accessed November 6, 2021.
2. Morgan IG, French AN, Ashby RS, et al. The epidemics of
myopia: Aetiology and prevention.
Prog Retin Eye Res 2018; 62:134–149.
3. Holden BA, Fricke TR, Wilson DA, et al. Global prevalence of
myopia and high
myopia and temporal trends from 2000 through 2050.
Ophthalmology 2016; 123:1036–1042.
4. Yusufu M, Bukhari J, Yu X, et al. Challenges in eye care in the Asia-Pacific region.
Asia Pac J Ophthalmol (Phila) 2021; 10:423–429.
5. Dolgin E. The
myopia boom.
Nature 2015; 519:276–278.
6. Morgan IG, Ohno-Matsui K, Saw SM.
Myopia.
Lancet 2012; 379:1739–1748.
7. Morgan IG, Iribarren R, Fotouhi A, Grzybowski A. Cycloplegic refraction is the gold standard for epidemiological studies.
Acta Ophthalmol 2015; 93:581–585.
9. Wu JF, Bi HS, Wang SM, et al. Refractive error, visual acuity and causes of vision loss in children in Shandong,
China. The Shandong Children Eye Study.
PLoS One 2013; 8:e82763.
10. Hu YY, Wu JF, Lu TL, et al. Effect of cycloplegia on the refractive status of children: the Shandong children eye study.
PLoS One 2015; 10:e0117482.
11. Sun YY, Wei SF, Li SM, et al. Cycloplegic refraction by 1% cyclopentolate in young adults: is it the gold standard? The Anyang University Students Eye Study (AUSES).
Br J Ophthalmol 2019; 103:654–658.
12. Xu L, Zhuang Y, Zhang G, et al. Design, methodology, and baseline of whole city-million scale children and adolescents
myopia survey (CAMS) in Wenzhou,
China.
Eye Vis (Lond) 2021; 8:31.
13. Lin LL, Shih YF, Hsiao CK, Chen CJ. Prevalence of
myopia in Taiwanese schoolchildren: 1983 to 2000.
Ann Acad Med Singapore 2004; 33:27–33.
14. Saw SM, Carkeet A, Chia KS, et al. Component dependent risk factors for ocular parameters in Singapore Chinese children.
Ophthalmology 2002; 109:2065–2071.
15. Tsai TH, Liu YL, Ma IH, et al. Evolution of the prevalence of
myopia among Taiwanese schoolchildren: a review of survey data from 1983 through 2017.
Ophthalmology 2021; 128:290–301.
16. Yam JC, Tang SM, Kam KW, et al. High prevalence of
myopia in children and their parents in Hong Kong Chinese population: the Hong Kong children eye study.
Acta Ophthalmol 2020; 98:e639–e648.
17. Guo X, Fu M, Ding X, et al. Significant axial elongation with minimal change in refraction in 3- to 6-year-old Chinese preschoolers: the Shenzhen kindergarten eye study.
Ophthalmology 2017; 124:1826–1838.
18. He M, Xiang F, Zeng Y, et al. Effect of time spent outdoors at school on the development of
myopia among children in
China: a randomized clinical trial.
JAMA 2015; 314:1142–1148.
19. Lan W, Zhao F, Lin L, et al. Refractive errors in 3–6 year-old Chinese children: a very low prevalence of
myopia?
PLoS One 2013; 8:e78003.
20. Ma Y, Zou H, Lin S, et al. Cohort study with 4-year follow-up of
myopia and refractive parameters in primary schoolchildren in Baoshan District, Shanghai.
Clin Exp Ophthalmol 2018; 46:861–872.
21. Morgan IG, He M, Rose KA. Epidemic of pathological
myopia: what can laboratory studies and epidemiology tell us?
Retina 2017; 37:989–997.
22. Sankaridurg PR, Holden BA. Practical applications to modify and
control the development of ametropia.
Eye (Lond) 2014; 28:134–141.
23. Chua SY, Sabanayagam C, Cheung YB, et al. Age of
onset of
myopia predicts risk of high
myopia in later childhood in myopic Singapore children.
Ophthalmic Physiol Opt 2016; 36:388–394.
24. Ohno-Matsui K, Wu PC, Yamashiro K, et al. IMI Pathologic
Myopia.
Invest Ophthalmol Vis Sci 2021; 62:5.
25. Xu L, Wang YX, Li YB, et al. Causes of blindness and visual impairment in urban and rural areas in Beijing: the Beijing Eye Study.
Ophthalmology 2006; 1134–1144.
26. Iwase A, Araie M, Tomidokoro A, et al. Prevalence and causes of low vision and blindness in a Japanese adult population: the Tajimi Study.
Ophthalmology 2006; 113:1354–1362.
27. Li T, Zhou XD. Causes and five-year proportion of new irreversible visual impairment in Jinshan District, Shanghai, from 2009–2018.
J Ophthalmol 2021; 2021:8873283.
28. Morgan IG, Wu PC, Ostrin LA, et al. IMI risk factors for
myopia.
Invest Ophthalmol Vis Sci 2021; 62:3.
29. Mountjoy E, Davies N, Plotnikov D, et al. Education and
myopia: a Mendelian randomization study.
BMJ 2018; 361:k2022.
30. Cuellar-Partida G, Lu Y, Kho PF, et al. Assessing the genetic predisposition of education on
myopia: a Mendelian randomization study.
Genet Epidemiol 2016; 40:66–72.
31. Plotnikov D, Williams C, Atan D, et al. Effect of education on
myopia: evidence from the United Kingdom ROSLA 1972 Reform.
Invest Ophthalmol Vis Sci 2020; 61:7.
32. Ding X, Hu Y, Morgan I, He M. Exposure to the life of a school child rather than age determines myopic shifts in refraction in school children.
Invest Ophthalmol Vis Sci.
33. Morgan IG, Rose KA.
Myopia and international educational performance.
Ophthalmic Physiol Opt 2013; 33:329–338.
34. Jones LA, Sinnott LT, Mutti DO, et al. Parental history of
myopia, sports and outdoor activities, and future
myopia.
Invest Ophthalmol Vis Sci 2007; 48:3524–3532.
35. Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of
myopia in children.
Ophthalmology 2008; 115:1279–1285.
36. Xiong S, Sankaridurg P, Naduvilath T, et al. Time spent in outdoor activities in relation to
myopia prevention and
control: a meta-analysis and systematic review.
Acta Ophthalmol 2017; 95:551–566.
37. Rose KA, Morgan IG, Smith W, et al.
Myopia, lifestyle, and schooling in students of Chinese ethnicity in Singapore and Sydney.
Arch Ophthalmol 2008; 126:527–530.
38. Ashby R, Ohlendorf A, Schaeffel F. The effect of ambient illuminance on the development of deprivation
myopia in chicks.
Invest Ophthalmol Vis Sci 2009; 50:5348–5354.
39. Ashby RS, Schaeffel F. The effect of bright light on lens compensation in chicks.
Invest Ophthalmol Vis Sci 2010; 51:5247–5253.
40. Smith EL 3rd, Hung LF, Arumugam B, Huang J. Negative lens-induced
myopia in infant monkeys: effects of high ambient lighting.
Invest Ophthalmol Vis Sci 2013; 54:2959–2969.
41. Smith EL 3rd, Hung LF, Huang J. Protective effects of high ambient lighting on the development of form-deprivation
myopia in rhesus monkeys.
Invest Ophthalmol Vis Sci 2012; 53:421–428.
42. Gurevik U, Kara H, Yasar E. Effect of methylphenidate as a dopaminergic agent on
myopia: pilot study.
Int J Clin Pract 2021; 75:e14665.
43. Jin JX, Hua WJ, Jiang X, et al. Effect of outdoor activity on
myopia onset and
progression in school-aged children in northeast
China: the Sujiatun eye care study.
BMC Ophthalmol 2015; 15:73.
44. Wu PC, Tsai CL, Wu HL, et al. Outdoor activity during class recess reduces
myopia onset and
progression in school children.
Ophthalmology 2013; 120:1080–1085.
45. Wu PC, Chen CT, Chang LC, et al. Increased time outdoors is followed by reversal of the long-term trend to reduced visual acuity in Taiwan primary school students.
Ophthalmology 2020; 127:1462–1469.
46. Hobday R.
Myopia and daylight in schools: a neglected aspect of public health?
Perspect Public Health 2016; 136:50–55.
47. Hua WJ, Jin JX, Wu XY, et al. Elevated light levels in schools have a protective effect on
myopia.
Ophthalmic Physiol Opt 2015; 35:252–262.
48. Cohen Y, Iribarren R. Light intensity in nursery schools: a possible factor in refractive development.
Asia-Pacific J Ophthalmol (Phila) 2022; 11:66–71.
49. Zhou Z, Chen T, Wang M, et al. Pilot study of a novel classroom designed to prevent
myopia by increasing children's exposure to outdoor light.
PLoS One 2017; 12:e0181772.
50. Jiang Y, Zhu ZT, Tan XP, et al. Effect of repeated low-level red-light therapy in
myopia control in children: A multicenter randomized controlled trial.
Ophthalmology 2021; Online in press, Dec 1:S0161-6420(21)00916-7. doi: 10.1016/j.ophtha.2021.11.023.
51. Dirani M, Crowston JG, Wong TY. From reading books to increased smart device screen time.
Br J Ophthalmol 2019; 103:1–2.
52. Lanca C, Saw SM. The association between digital screen time and
myopia: A systematic review.
Ophthalmic Physiol Opt 2020; 40:216–229.
53. Foreman J, Salim AT, Praveen A, et al. Association between digital smart device use and
myopia: a systematic review and meta-analysis.
Lancet Digit Health 2021; 3:e806–e818.
54. Jonas JB, Ang M, Cho P, et al. IMI prevention of
myopia and its
progression.
Invest Ophthalmol Vis Sci 2021; 62:6.
55. Wildsoet CF, Chia A, Cho P, et al. IMI - interventions for controlling
myopia onset and
progression report.
Invest Ophthalmol Vis Sci 2019; 60:M106–M131.
56. Vincent SJ, Cho P, Chan KY, et al. CLEAR - Orthokeratology.
Cont Lens Anterior Eye 2021; 44:240–269.
57. Chamberlain P, Peixoto-de-Matos SC, Logan NS, et al. A 3-year randomized clinical trial of misight lenses for
myopia control.
Optom Vis Sci 2019; 96:556–567.
58. Lam CS, Tang WC, Lee PH, et al.
Myopia control effect of defocus incorporated multiple segments (DIMS) spectacle lens in Chinese children: results of a 3-year follow-up study.
Br J Ophthalmol 2021; Published online ahead of print. doi:10.1136/bjophthalmol-2020-317664.
59. Bao J, Yang A, Huang Y, et al. One-year
myopia control efficacy of spectacle lenses with aspherical lenslets.
Br J Ophthalmol 2021; Published online ahead of print. doi:10.1136/bjophthalmol-2020-318367.
60. Chia A, Lu QS, Tan D. Five-year clinical trial on atropine for the treatment of
myopia 2:
myopia control with atropine 0.01% eyedrops.
Ophthalmology 2016; 123:391–399.
61. Yam JC, Jiang Y, Tang SM, et al. Low-concentration atropine for
myopia progression (LAMP) study: a randomized, double-blinded, placebo-controlled trial of 0.05%, 0.025%, and 0.01% atropine eye drops in
myopia control.
Ophthalmology 2019; 126:113–124.
62. Kastner J. The problem with Taiwanese eyes. The Diplomat. Available at
https://thediplomat.com/tag/myopia/. Published on March 12, 2015. Accessed November 6, 2021.
63. Fang YT, Chou YJ, Pu C, et al. Prescription of atropine eye drops among children diagnosed with
myopia in Taiwan from 2000 to 2007: a nationwide study.
Eye (Lond) 2013; 27:418–424.
64. Chew SJ, Chia SC, Lee LK. The pattern of
myopia in young Singaporean men.
Singapore Med J 1988; 29:201–211.
65. Karuppiah V, Wong L, Tay V, et al. School-based programme to address childhood
myopia in Singapore.
Singapore Med J 2021; 62:63–68.
66. 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; 6:28531.
67. Li SM, Kang MT, Peng XX, et al. Efficacy of Chinese eye exercises on reducing accommodative lag in school-aged children: a randomized controlled trial.
PLoS One 2015; 10:e0117552.
68. Feng SY. The evolution of shadow education in
China. From emergence to capitalisation.
Hungarian Educ Res J 2021; 2:89–100.
69. Tsai DC, Fang SY, Huang N, et al.
Myopia development among young schoolchildren: the
myopia investigation study in Taipei.
Invest Ophthalmol Vis Sci 2016; 57:6852–6860.
70. Chiang WY, Chen YW, Liu YP, et al. Early age of the first myopic spectacle prescription, as an indicator of early
onset of
myopia, is a risk factor for high
myopia in adulthood.
J Ophthalmol 2021; 2021: 6612116.
71. Kim SW, Lee JH. Private tutoring and demand for education in South Korea.
Educ Dev Cult Change 2010; 58:259–296.
72. Choi H, Choi A. Regulating private tutoring consumption in Korea: Lessons from another failure.
Int J Educ Dev 2016; 49:144–156.
73. Three-Fourths of South Korean Students Get Private Tutoring: Survey. Available at
https://en.yna.co.kr/view/AEN20200429008900315. Accessed November 6, 2021.
74. Private Tutoring Thrives During Debate Over Efficacy of Public Education. Available at
https://en.yna.co.kr/view/AEN20070507003200315. Accessed November 6, 2021.
75. Kretschmer F.
China Clamps Down on Cram Schools, but South Korea is a Different Story. Available at
https://www.dw.com/en/china-clamps-down-on-cram-schools-but-south-korea-is-a-different-story/a-58760942. Accessed November 6, 2021.
76. Jung SK, Lee JH, Kakizaki H, Jee D. Prevalence of
myopia and its association with body stature and educational level in 19-year-old male conscripts in Seoul, South Korea.
Invest Ophthalmol Vis Sci 2012; 53:5579–5583.
77. Entrich SR. Shadow Education and Social Inequalities in Japan, Chapter 10, Recent Changes to Japanese Education; the Yutori Reforms. doi: 10.1007/978-3-319-69119-0_10
78. Ishiko S, Kagokawa H, Nishikawa N, et al. Impact of the pressure-free Yutori education program on
myopia in Japan.
J Clin Med 2021; 10:4229.
79. Organization for Economic Cooperation and Development. Strong Performers and Successful Reformers In Education – Lessons from PISA for Japan. Available at
https://www.oecd.org/education/school/programmeforinternationalstudentassessmentpisa/strongperformersandsuccessfulreformersineducation-lessonsfrompisaforjapan.htm. Accessed November 6, 2021.
80. Organization for Economic Cooperation and Development. Country Note Japan. Available at
https://www.oecd.org/pisa/publications/PISA2018_CN_JPN.pdf. Accessed November 6, 2021.
81. Yotsukura E, Torii H, Inokuchi M, et al. Current prevalence of
myopia and association of
myopia with environmental factors among schoolchildren in Japan.
JAMA Ophthalmol 2019; 137:1233–1239.
82. He M, Zeng J, Liu Y, et al. Refractive error and visual impairment in urban children in southern
china.
Invest Ophthalmol Vis Sci 2004; 45:793–799.
83. 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.
85. National Health and Family Planning Commission. 13
th National Eye Care Plan. Available at
https://www.iapb.org/learn/resources/china-five-year-national-plan-for-eye-health-2016-2020/. Accessed November 6, 2021.
86. Wei X. More Vision Needs to Help Reduce
Myopia. Available at
http://www.chinadaily.com.cn/a/201808/29/WS5b85eb0da310add14f3884cc.html. Accessed November 6, 2021.
87. Ministry of Education of the People's Republic of
China. Notice of Ministry and Eight Other Departments on Issuing the Implementation Plan of Comprehensive
Control of
Myopia in Children and Adolescents. Available at
http://www.moe.gov.cn/srcsite/A17/moe_943/s3285/201808/t20180830_346672.html. Accessed November 6, 2021.
88. Ministry of Education of the People's Republic of
China. Opinions of Further Reducing the Burden of Student's Homework and Off-Campus Training in Compulsory Education. Available at
http://www.moe.gov.cn/fbh/live/2021/53799/mtbd/202110/t20211026_575220.html. Accessed November 6, 2021.
89. Morgan IG. What public policies should be developed to deal with the epidemic of
myopia?
Optom Vis Sci 2016; 93:1058–1060.
90. Yu MQ. [Get Students “Wild” in the First 10 Minutes of Lesson.] [
China Education News Network]. Available at
http://www.jyb.cn/rmtzgjsb/202104/t20210427_551270.html. Published on April 27, 2021. Accessed November 6, 2021.
91. Liang YY, Kee CS. Risk factors for
myopia in 2 Hong Kong school systems. A pilot study.
Asia-Pacific J Ophthalmol (Phila) 2022; 11:19–26.
93. Barker JE, Semenov AD, Michaelson L, et al. Less-structured time in children's daily lives predicts self-directed executive functioning.
Front Psychol 2014; 5:1–16.
94. Organization for Economic Cooperation and Development. The Nature of Learning. Available at
https://www.oecd.org/education/ceri/50300814.pdf. Accessed November 6, 2021.
95. United Nations Department of Economic and Social Affairs. Sustainable Development. Available at
https://sdgs.un.org/goals/goal4. Accessed December 3, 2021.
96. International Agency for the Prevention of Blindness. United Nations General Assembly Commits Countries to Eye Care for All by 2030. Available at
https://www.iapb.org/news/un-resolution-vision/. Accessed December 3, 2021.
