Identifying the key factors influencing the cause of blindness and visual impairment in Sierra Leone: A mixed-methods analysis of epidemiological and socioeconomic determinants

Sierra Leone, a post-conflict nation in West Africa, bears a disproportionately high burden of blindness and visual impairment (BVI), severely impacting human capital and socioeconomic development; this study aimed to identify and analyze the key factors influencing the causes of BVI to inform effective public health interventions. A nationwide, population-based cross-sectional survey was conducted utilizing two-stage cluster random sampling in accordance with WHO’s Rapid Assessment of Avoidable Blindness (RAAB) methodology, examining 5,118 participants aged ≥50 years across all four geographic regions, complemented by 32 semi-structured interviews to explore contextual and socioeconomic barriers. The prevalence of blindness (presenting visual acuity less than 3/60) was 4.2% (95% CI: 3.7-4.7), with major causes being cataract (58.3%), glaucoma (14.2%), posterior segment diseases (11.5%), corneal opacities (7.1%), and uncorrected refractive error (5.4%); over 70% of all blindness was avoidable, with key influencing factors including extreme poverty, a critical shortage of ophthalmic personnel, geographical inaccessibility, low surgical output, and persistent cultural beliefs. In conclusion, while cataract remains the leading cause, the high prevalence is sustained by a complex interplay of systemic healthcare weaknesses, profound poverty, and deeply entrenched social barriers, necessitating a multi-faceted national eye health strategy that integrates service delivery with poverty reduction and health education to eliminate avoidable blindness.