Refractive errors remain one of the most common and preventable causes of visual impairment in children, contributing substantially to avoidable morbidity during the most formative years of life. Uncorrected refractive errors not only impair visual development but also disrupt academic performance, reduce participation in daily activities, and diminish overall quality of life [1,2]. Routine vision screening among school-aged children enables early detection and timely correction, thereby preventing long-term disability and reducing the burden on families and educational systems [3,4]. Refractive error is recognized as the second leading cause of treatable blindness worldwide and continues to be a major contributor to childhood visual impairment in India. Reports suggest that 16.3% to 37% of childhood blindness in the country is avoidable through appropriate identification and management [5,6]. Myopia, in particular, has emerged as a major global public health challenge. Several Southeast Asian countries report dramatically rising rates of childhood myopia, and similar trends are being observed across urban and semi-urban regions of India [7,8]. Limited awareness, delayed health-seeking behaviour, and underdiagnosis—especially in rural and underserved areas further amplify the burden of uncorrected refractive errors. Barriers such as inadequate access to eye-care services, financial constraints, and misconceptions regarding spectacle use contribute to a high proportion of undetected cases. Against this backdrop, the present study aims to determine the prevalence and distribution of refractive errors among school-going children aged 10 to 17 years in the Vizianagaram district of Andhra Pradesh. By assessing refractive patterns within this population, the study seeks to provide evidence to guide future school-based screening strategies and strengthen early intervention services.

Study Design A school-based cross-sectional study was conducted to assess the prevalence and pattern of refractive errors among children aged 10–17 years in the Vizianagaram district of Andhra Pradesh. Study Setting and Programme Background The screening was carried out under the School Health Programme of the National Programme for Control of Blindness (NPCB), which aims to detect and manage refractive errors in school-aged children. Both government and private schools located in the Vizianagaram district were included in the screening activity. Study Duration The study was conducted over a four-month period, from August 2024 to November 2024. Study Population The target population comprised school-going children aged 10 to 17 years enrolled in the selected schools of the district. Inclusion Criteria Students aged 10–17 years who were present on the day of school screening. Children whose parents or guardians provided informed consent. Students who assented to participate. Exclusion Criteria Children absent during the screening visit. Students with active ocular infections precluding examination. Children with a history of ocular surgery or trauma (self-reported or based on school records). Students unwilling to participate. Sampling and School Selection A total of 27 schools (government and private) were selected as part of the NPCB screening schedule. All eligible children present on the screening day were included, ensuring complete enumeration rather than sampling. Screening Procedure The screening process consisted of the following steps: 1. Visual Acuity Assessment Visual acuity was measured using a standard Snellen’s chart placed at 6 meters. A visual acuity of <6/9 in either eye was classified as subnormal and considered for further evaluation. 2. Subjective Verification Students with visual acuity <6/9 underwent subjective refraction by trained optometrists. Retinoscopy and refinement were performed where indicated. 3. Cycloplegic Refraction Cycloplegia was induced in younger children and in those suspected to have latent hyperopia. Cycloplegic retinoscopy was performed according to standard NPCB guidelines. 4. Classification of Refractive Errors Refractive errors were categorized based on the Refractive Error Study in Children (RESC) criteria [9]: Myopia: Spherical equivalent ≤ –0.50 Diopters (D) Hyperopia: Spherical equivalent ≥ +2.00 D Astigmatism: Cylindrical error ≥ ±0.75 D Data Collection Tools A structured screening format issued under NPCB was used to record: Demographic details (age, sex, class) Visual acuity findings Refractive error type and magnitude Spectacle usage status Referral needs for other ocular conditions Referral Protocol Children with refractive errors requiring correction were recorded for spectacle provision. Students with visual acuity reduction not attributable to refractive errors or those with other ocular conditions were referred to the tertiary eye care hospital for further evaluation. Ethical Considerations Administrative permission was obtained from the District Medical and Health Office and school authorities. Informed consent from parents/guardians and verbal assent from children were obtained. Confidentiality of participant data was maintained. The study adhered to the principles of the Declaration of Helsinki. Statistical Analysis Data were entered into Microsoft Excel and analyzed using descriptive statistics. Prevalence was expressed in percentages. Age-wise and sex-wise distribution tables were generated. Refractive error patterns were summarized using frequencies and proportions.

A total of 5893 students of age group between 10-17 years have been screened for refractive errors. Mean age of study population is 13.63, ±SD 1.79. Out of 5893 students, 2330 were boys and 3563 were girls. Among 5893 students who have been screened, 416(7.05%) students were found to have defective vision i.e. visual acuity less than 6/9, out of which 386 students have defective vision due to refractive errors. The prevalence of refractive errors was found to be 6.5%. Defective vision due to other causes was found in 30(0.5%) students and they are referred to the tertiary eye care hospital for further evaluation. TABLE 1: Sex distribution in children with refractive errors. GENDER FREQUENCY PERCENTAGE BOYS 109 28.23% GIRLS 277 71.7% TOTAL 386 100% Out of 386 children having diagnosed with refractive errors, only 26 (6.73%) children were using glasses. This gives us an inference that 360 (93.26%) students were not aware that they have refractive error. In our study, most common refractive error was found to be myopia which was present in 326(84%) children followed by astigmatism in 59(15%) children followed by hypermetropia in 1(0.25%) child. Myopia and astigmatism were more common among girls compared to boys. It was observed that there is an increased incidence of myopia among the older age group of 14-17 years which was around 46.37%. TABLE 2: Distribution of refractive errors among the children. TOTAL MYOPIA ASTIGMATISM HYPERMETROPIA FREQUENCY 386 326 59 1 PERCENTAGE 100% 84% 15% 0.20% TABLE 3: Age wise distribution of refractive errors Age Myopia Hypermetropia Astigmatism Total 10 8 0 0 8 11 45 0 9 54 12 49 0 4 53 13 45 0 6 51 14 74 1 12 87 15 61 0 15 76 16 30 0 6 36 17 14 0 7 21 TABLE 4: Age group distribution of refractive errors. Age group Myopia Hypermetropia Astigmatism 10-13 147(38.08%) 0 19 14-17 179(46.37%) 1 40

The present study demonstrated a refractive error prevalence of 6.5% among school-going children aged 10–17 years in Vizianagaram district, a finding closely aligned with reports from Karnataka (6.4%) and East Sikkim (6.7%) [10,14]. This similarity suggests a stable and comparable burden of childhood refractive errors across different regions of India. A notable observation in the current study was the significantly higher proportion of affected girls (71.7%) compared with boys (28.2%), a trend also reported in earlier Indian studies [11,12]. However, this pattern contrasts with the findings of Prabha and Meriton Stanely, who observed no gender-based difference in refractive error distribution [13]. Such variability highlights the possible influence of region-specific behavioural, environmental or educational factors on visual health. Myopia emerged as the predominant refractive error, accounting for 84% of all cases, followed by astigmatism (15%) and minimal hypermetropia (0.25%). This distribution mirrors the pattern documented in the East Sikkim study, where myopia was similarly dominant [14]. The high proportion of myopia in the present cohort may reflect increased academic pressure, prolonged reading tasks and escalating screen exposure—factors consistently associated with childhood onset myopia in global literature [7-9]. The rise in myopia with advancing age, particularly among children aged 14–17 years, further supports the link between cumulative near-work activities and refractive progression. An alarming finding from this study was that 93.26% of children with refractive errors were unaware of their visual impairment and were not using corrective spectacles. A similarly low spectacle-use rate has been reported in earlier Indian studies, reflecting persistent gaps in awareness, accessibility and cultural acceptance of spectacles, particularly in rural settings [11]. This large proportion of uncorrected refractive errors underscores the urgent need to strengthen school-based screening and enhance community-level awareness regarding the importance of early detection and correction. Limitations This study was limited by its cross-sectional design, which restricts causal interpretation. Screening was conducted only in selected schools participating in the NPCB programme, potentially limiting representation of the entire district. Cycloplegic refraction could not be performed uniformly across all age groups due to feasibility constraints. The reliance on single-day school visits may have resulted in missing children absent on screening days. Detailed data regarding duration of near-work activities, outdoor exposure time, socioeconomic status and parental awareness were not captured, restricting deeper interpretation of associated factors. Despite these limitations, the large sample provides meaningful insights into refractive error burden among school-aged children.

The study demonstrates a considerable burden of uncorrected refractive errors among school-going children in Vizianagaram, with myopia being the predominant concern and a substantial proportion of students remaining unaware of their visual impairment. These findings highlight the need for strengthened, periodic school-based screening, affordable spectacle provision, and structured awareness initiatives targeting parents and teachers. Integrating vision screening into routine school health services and empowering primary health workers and teachers with basic training can enable timely detection and referral. Reinforcing follow-up and referral pathways is essential to prevent avoidable visual disability and ensure that children receive appropriate correction at the earliest opportunity.

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