Cost effectiveness and cost utility of an organized screening programme for glaucoma.

PURPOSE To assess the cost effectiveness and cost utility of an organized screening programme for glaucoma. The previous cost-effectiveness studies of screening show inconsistent results, and the cost utility of screening has not been assessed. METHODS An organized screening programme was simulated using Markov modelling in a population aged 50-79 years at 5 year intervals. The programme ended when the subjects reached the age of 80 years. The comparator was opportunistic case finding. The main outcome measures were cases and years of severe visual disability avoided, quality-adjusted life years (QALYs) gained and direct healthcare and non-healthcare costs. RESULTS The incremental cost of 1 year of avoided visual disability by screening was euro32 602. The cost of one QALY gained by screening was euro9023 with a discount rate of 5%. During the average 20 year time horizon considered, the cumulative incremental costs of screening in a population of 1 million people would be euro30 million, producing 3360 incremental QALYs and 930 years of avoided visual disability for 701 persons. The results were sensitive to the estimates of several parameters, especially screening cost and specificity of screening tests (96-99% specificity required). CONCLUSION An organized screening programme could be a cost-effective strategy especially in older age groups, in which screening is clearly more likely to be acceptable to decision makers at any level in terms of their willingness to pay for a QALY. Modelling includes some uncertainty especially concerning the specificity of diagnostic tests and screening cost.