Prevalence, coverage and effective coverage of refractive error in all age groups in Theni District, India

Abstract

Purpose

To estimate prevalence of distance and near vision refractive errors (RE) across all age groups in Theni district, Tamil Nadu, India, using the World Health Organization’s (WHO) visual acuity threshold. To report refractive error coverage for distance and near vision (REC_D and REC_N) and effective REC (eREC_D and eREC_N), and to examine association with socio-demographic variables.

Design

Population-based cross-sectional study

Methods

In 2017–2018 we recruited 24,327 participants through random cluster sampling. Basic eye examinations were performed for those below 40 years, while those ≥40 years, along with referrals from those <40 underwent full eye examinations, resulting in 16,963 participants.

Results

The prevalence of distance RE was 12%, increasing with age and tripling among those >60 years. Females had a higher prevalence (p < 0.001). Overall, REC_D was 35.5% but declined with age, dropping to 26% in the 61–70 age group. Coverage was higher among urban populations, better educated individuals, pre-school-age children, and students. eREC_D was 33.4%, with a small relative quality gap of 5.9%.

The prevalence of near vision RE was 30%, increasing with age but declining beyond 50 years. Females and rural populations had higher prevalence (p < 0.001). Overall, REC_N was alarmingly low at 15.9%, improving to 24% in those >70 years, with higher coverage in males and urban populations (p < 0.001). eREC_N was 9.6%, with a quality gap of 39.8%.

Conclusion

Prevalence rates, REC and eREC, can serve as the basis for planning and tracking progress toward WHO’s global target of a 40 percentage-point increase in eREC in Theni District.