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Hernandez et al. (492) systematically review current evidence on the cost-effectiveness of screening strategies for open-angle glaucoma (OAG). After deciding on the inclusion and exclusion criteria, they have conducted a highly sensitive electronic search. Data extraction was focused on two key areas, namely the results of the economic evaluations in terms of estimates on costs and effects, and the methods used to derive the results and their interpretation. Furthermore, the quality of the studies was assessed. They identified 496 titles relevant to the study subject and retrieved from them 67 full text papers. Finally, four of them met the eligibility criteria and were further studied. These four eligible reports came from the US, Canada and the UK, the latest of them published in 1997. The included studies were broadly similar with respect to population, screening and treatment costs. The results of the cost-utility analyses were difficult to interpret because of the different years and countries to which the data related and the differences in technologies considered and outcome measures used. None of the studies could be helpful enough for the decision of adopting screening for OAG. That is because there have been developments in diagnostic tests as well as new treatments available, so calculations made ten or more years ago can not reflect present conditions. Furthermore, none of the studies was able to tell whether any form of screening would be worthwhile. An issue that the authors did not include in their discussion is that research in the field of glaucoma screening should be done by stage of the disease since the latter is a key determinant of cost-effectiveness. Many of these issues were discussed in the recent WGA Consensus on Glaucoma Screening that will be soon published. This study by Hernandez et al., after a thorough and systematic work, stresses that there is an insufficient evidence base for judging whether screening for OAG should take place, and if it should, how it should be performed.