Epidemiology of Refractive Error in Ghana: A Systematic Review and Meta-Analysis.

Abstract

Purpose: To synthesise the population-based prevalence of myopia, hyperopia and astigmatism in Ghana and evaluate the methodological drivers of heterogeneity within the existing epidemiological literature.

Recent findings: A systematic review and meta-analysis of nine eligible population-based cross-sectional studies (n = 7153 participants, age range 5-70 years) was conducted. Due to substantial inter-study heterogeneity, pooled estimates should be interpreted as weighted averages rather than definitive national prevalences. The pooled prevalence was approximately 3.1% (95% CI: 1.9% to 5.0%) for myopia, 2.2% (95% CI: 1.1% to 4.4%) for hyperopia and 1.7% (95% CI: 0.7% to 3.9%) for astigmatism. Prediction intervals were wide, reflecting extreme between-study variance. Subgroup analyses revealed that myopia prevalence was significantly higher in urban (3.1%) and mixed settings (4.7%) compared with rural areas (0.8%; 95% CI: 0.4% to 1.6%). Furthermore, studies omitting cycloplegia severely underestimated hyperopia prevalence (1.3%) compared to the single cohort utilising cycloplegic refraction (4.6%). Continuous meta-regression indicated a positive correlation between hyperopia and advancing age, while apparent temporal declines in hyperopia and astigmatism may reflect methodological shifts rather than true epidemiological trends. The findings suggest higher myopia prevalence in urban and mixed settings and indicate that cycloplegic use may influence reported hyperopia prevalence estimates. Future epidemiological studies would benefit from standardised cycloplegic protocols and harmonised refractive error definitions to improve comparability of prevalence estimates.