Strategies for cataract and uncorrected refractive error case finding in India: Costs and cost-effectiveness at scale.

Background: India has the largest number of individuals suffering from visual impairment and blindness in the world. Recent surveys indicate that demand-based factors prevent more than 80% of people from seeking appropriate eye services, suggesting the need to scale up cost-effective case finding strategies. We assessed total costs and cost-effectiveness of multiple strategies to identify and encourage people to initiate corrective eye services. Methods: Using administrative and financial data from six Indian eye health providers, we conduct a retrospective micro-costing analysis of five case finding interventions that covered 1·4 million people served at primary eye care facilities (vision centers), 330,000 children screened at school, 310,000 people screened at eye camps and 290,000 people screened via door-to-door campaigns over one year. For four interventions, we estimate total provider costs, provider costs attributable to case finding and treatment initiation for uncorrected refractive error (URE) and cataracts, and the societal cost per DALY averted. We also estimate provider costs of deploying teleophthalmology capability within vision centers. Point estimates were calculated from provided data with confidence intervals determined by varying parameters probabilistically across 10,000 Monte Carlo simulations. Findings: Case finding and treatment initiation costs are lowest for eye camps (URE: $8·0 per case, 95% CI: 3·4-14·4; cataracts: $13·7 per case, 95% CI: 5·6-27·0) and vision centers (URE: $10·8 per case, 95% CI: 8·0-14·4; cataracts: $11·9 per case, 95% CI: 8·8-15·9). Door-to-door screening is as cost-effective for identifying and encouraging surgery for cataracts albeit with large uncertainty ($11·3 per case, 95% CI: 2·2 to 56·2), and more costly for initiating spectacles for URE ($25·8 per case, 95% CI: 24·1 to 30·7). School screening has the highest case finding and treatment initiation costs for URE ($29·3 per case, 95% CI: 15·5 to 49·6) due to the lower prevalence of eye problems in school aged children. The annualized cost of operating a vision center, excluding procurement of spectacles, is estimated at $11,707 (95% CI: 8,722-15,492). Adding teleophthalmology capability increases annualized costs by $1,271 per facility (95% CI: 181 to 3,340). Compared to baseline care, eye camps have an incremental cost-effectiveness ratio (ICER) of $143 per DALY (95% CI: 93-251). Vision centers have an ICER of $262 per DALY (95% CI: 175-431) and were able to reach substantially more patients than any other strategy. Interpretation: Policy makers are expected to consider cost-effective case finding strategies when budgeting for eye health in India. Screening camps and vision centers are the most cost-effective strategies for identifying and encouraging individuals to undertake corrective eye services, with vision centers likely to be most cost-effective at greater scale. Investment in eye health continues to be very cost-effective in India. Funding: The study was funded by the Seva Foundation.