European Journal of Cardiovascular Medicine

India was the pioneer in launching the National Program for Control of Blindness in 1976, with the objective of reducing the prevalence of blindness to 0.3% by the year 2020. According to estimates from the National Blindness and Visual Impairment Survey conducted 2015-19, there are around 4.9 million blind individuals and 32.9 million with visual impairment in the country1. Addressing refractive errors is crucial for improving visual health and enhancing the quality of life for affected individuals 2,3. Uncorrected refractive error is the primary cause of avoidable vision impairment and ranks as the second leading cause of blindness worldwide4. Although easily treatable, but owing to limited access to corrective measures like spectacles, it contributes to a substantial burden of visual impairment globally 4,5.

Colour vision deficiency (CVD), commonly known as colour blindness, refers to the inability to differentiate certain shades of colour. This condition is either congenital, primarily inherited and predominantly affects males and sometimes acquired, resulting from diseases or medications5,6,14. Studies estimated 1-8% of men and 0.4-3% of women experiencing CVD7,8,9,10. While the condition does not pose significant challenges in everyday life, it can create serious challenges in certain professions, impacting safety and financial stability and often remains undetected until a individual undergoes visual examinations mostly for jobs 11,12.  These visual

impairments of Colour vision deficiency and refractive errors may lead to difficulties in reading, participating in school, and social interactions among children. Children often compensate for poor eyesight by sitting closer to blackboards or squinting. Since they may struggle to express vision issues, regular screenings are essential. Early detection allows for timely interventions, improving visual health and academic performance13,18. This can be achieved by screening among the students which in turn will help parents and educators make necessary adjustments to support learning 14,15,16,17.

OBJECTIVES

To determine the prevalence of visual impairment and colour blindness among primary school going children in the rural areas of Barpeta District

A descriptive, school-based cross-sectional study was conducted among school children aged 11 to 15 in Barpeta from November 2023 to February 2024. A total of 5 number of government schools were chosen with the highest number of enrollments in the field practice area of Fakhruddin Ali Ahmed Medical College, Barpeta (FAAMCH, Barpeta). After obtaining necessary ethics clearance and permissions, 1324 out of an estimated 1400 students were enrolled12. A pre-designed proforma was used to document the socioeconomic status of the students. All enrolled students were assessed for refractive errors and colour blindness using Snellen's visual acuity charts and Ishihara colour test books.

Students with ocular issues were referred to Ophthalmology OPD of FAAMCH, Barpeta. School authorities and parents were notified about the students' vision issues. Additionally, a list of affected students was shared with the District Early Intervention Centre (DEIC) to facilitate necessary follow-up actions.

Inclusion and Exclusion criteria

All children between 11 to 15 years with the consent of school authorities and their parents were enrolled. Children with congenital eye disease, corneal opacities or scars, previous history of ocular trauma and not consenting for any reason were not included in the study.

Data analysis:

The collected data was organized and analyzed using Microsoft Excel. Frequency distributions summarized categorical variables such as sex, age group, religion, family type, socioeconomic status, and parental education. The prevalence of ocular morbidities was calculated as proportions and displayed through frequency distribution tables, percentages, and graphical representations to effectively illustrate the distribution of variables and ocular morbidity prevalence.

A total of 1,324 children were enrolled in the study, with a gender distribution of 52% males (n=688) and 48% females (n=636), aged between 11 to 15 years. The majority of participants were identified as Hindu (85%), reflecting the cultural context of the region. Family structure analysis revealed that 76.9% of the participants came from nuclear families, while only 23.1% belonged to joint families. This predominance of nuclear families suggests a shift in family dynamics, which may influence the social and educational environment of the children.

Table 1. Table showing distribution of Study Variables (N=1324)

Socioeconomic status, assessed using the modified B.G. Prasad’s Scale, indicated that 34.4% of participants fell into the lower middle class category, with 33.4% from the upper lower class. This significant portion of the population may face economic challenges that could hinder access to healthcare and educational resources. The educational status of fathers was notably higher than that of mothers, reflecting traditional gender roles in education and employment (Table 1/Fig. 2)

Table2. Table showing ocular morbidities among the school students

Alarmingly, 85.2% of participants reported never having undergone an eye examination, highlighting a concerning gap in eye care access. The prevalence of colour blindness was found to be 2.7%, with a higher incidence in boys compared to girls. While the overall occurrence of significant ocular conditions appears low, the data indicates that some children may still experience visual impairments (Table 2). This underscores the urgent need for targeted interventions to improve eye health awareness and access to care.

Limitation

Since the current study focused solely on school-going children, its findings may not be broadly applicable. Comprehensive population-based studies are necessary to assess visual impairment in all children.

Refractive errors can lead to significant visual impairment if left untreated, yet 80% of visual impairment is preventable with early diagnosis and treatment. In this study, 158 school children (15.8%) from four schools were found to have at least one refractive error, similar to the 14% prevalence reported by Sabreena et al 18. Other studies have shown varying prevalence rates, including 5.6%, 6.43% , and 25.32% , which may be attributed to differences in methodology, age groups, and urban-rural settings19,20,21.The coherence of increasing prevalence of refractive errors with the age of the children was also observed by other researchers21,22,23 which may be due likely due to increased academic demands.

Current study concluded that girls had a higher prevalence of refractive errors compared to boys, which is consistent with other studies Singh et al. and Lin LL et al., which showed that girls had a much higher rate of refractive errors24 which interestingly is a contrast to the findings of the study done in Kerala amongst older school children25. The study also revealed that as families' socioeconomic status improved, the rate of refractive errors increased, showing consistency with research from by Saw et al.22 Additionally, the study showed that joint families had a higher prevalence of refractive errors however this finding was not supported by the other studies20,21,24.

Finally, 2.7% of children were identified as colour blind supported by other researchers26. Overall, these results highlight the multifaceted nature of refractive errors, necessitating comprehensive strategies for prevention and intervention.

The findings of the current study underscore the urgent need for targeted interventions to enhance eye health awareness and improve access to eye examinations for school children. . Socioeconomic factors and family structures identified in this study significantly influence the health and educational outcomes of these children. Children from lower socioeconomic backgrounds may face barriers in accessing eye care, impacting their academic performance and well-being.

To address these disparities, it is essential to implement community-based programs that promote eye health education and facilitate regular eye check-ups. Additionally, future research should be extended beyond the school-going children to encompass broader population-based studies. This comprehensive approach will help to identify the visual health needs of all children, regardless of their educational status. By understanding the full spectrum of visual health challenges, stakeholders can develop more effective strategies to promote optimal eye health resulting in improved health outcomes and educational success for children across diverse socioeconomic backgrounds.

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Available from: https://npcbvi.mohfw.gov.in/writeReadData/mainlinkFile/File341.pdf

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