Early detection and treatment of eye conditions is critical, as there is an increased risk of morbidity and mortality in children due to several conditions that cause blindness, including vitamin A deficiency, metabolic syndromes and retinoblastoma.14–19
Vision impairment in children can severely impact educational outcomes,6–10 contribute to low self-esteem,20 and future socio-economic potential.21
The prevalence of vision impairment and blindness varies considerably within, and between countries. Refractive error is the leading cause of vision impairment (MSVI) in school-aged children.22 Other common causes of vision impairment and blindness include cataract, retinopathy of prematurity, congenital ocular anomalies, corneal scarring, and cerebral visual impairment.5,23 The most prevalent avoidable causes of blindness are corneal scarring, cataract, and retinopathy of prematurity.23
The trends on the causes of childhood blindness have changed over the last 30 years. There has been a substantial shift in the leading causes of blindness in children in low-income countries due to the reduction of corneal blindness due to vitamin A deficiency and measles, and cataract is now the principal cause of avoidable blindness.18,24 In children, the leading causes of unavoidable blindness include genetic retinal conditions and congenital eye anomalies.4
In 2012, Naidoo et al.33 reported that in school-based surveys, refractive error is the leading cause of vision impairment in children,. With a prevalence ranging between 55-93%, 55% of children aged 5-15 years in Chile (Hyperopia the leading cause), and 93% of children in China aged 5-15 years (myopia the leading cause).30
The Lancet Commission4 reported the provision of spectacles to be one of the most effective health interventions for children, reducing the odds of failing a class by 44%, with an effect size greater than or equal to other health interventions.6–10
The cost-effectiveness of screening and correcting refractive errors in schoolchildren has been demonstrated in a variety of settings.34,35
The prevalence of myopia in children is rapidly increasing in many parts of the world.28
There are a number of eye conditions in children that have associated morbidity that do not cause vision impairment. Common non-vision impairing eye conditions in children include conjunctivitis (allergic and infectious), blepharitis and chalazion, which can require ongoing care and affect the quality of life of both the child and the parents.27
To address the eye health conditions in children, school-based eye health programmes have been adopted as they offer an effective,35–37 cost-effective model to deliver eye care to schoolchildren,35,39 and are efficient in respect to time and resources.12 School-based refraction and dispensing services increase access to spectacles.39 However, UNICEF reports gender parity is achieved in only 42% and 24% of lower secondary and upper secondary schools, respectively.44 As reported in the recent Lancet Commission5 It is also known that children who have vision impairment are less likely to attend school, and have poorer educational outcomes. It has been demonstrated that the provision of spectacles improves educational performance.6–10 While school-based services provide care to school-going children, this benefit is not realised by all children, particularly girls who are disproportionately represented in the out-of-school population.
References
The IAPB School Eye Health Workgroup has released these guidelines to help deliver standardised comprehensive eye health services to more than 700 million children attending schools around the world.
