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The issue of screening for open-angle glaucoma continues to be a controversial question for health authorities worldwide. This is primarily due to the relatively low prevalence of the disease along with its modest early impact on visual function and daily activities. Balancing these factors in a rigorous and quantitative manner is the realm of economic evaluation, with this report by Hernandez et al. (896) being an excellent example of employing these methods to address the question of whether screening programs for glaucoma represents an effective use of society's resources. The authors examine this question for the UK, and compare the current method of conducting an examination as part of the routine care visits to the optometrist (which we will call 'convenience screening') to strategies in which the person is invited to come to see an office based technician trained in glaucoma diagnostic methods (i.e., 'Tech' strategy), or an optometrist specializing in glaucoma (i.e., 'GO' strategy). The authors find that the GO strategy does not meet the standards for cost-effectiveness for any age group or expected prevalence of OAG in the population. The Tech strategy would be considered cost-effective, but only for people age 40-60, and then only if the expected prevalence was greater than 4% among people in this age group. Given that population based estimates in the US, Italy, and Australia have shown an expected prevalence of less than 1% in this age group, it is not likely that screening even in this limited group would meet accepted standards of cost-effectiveness. This is further confirmed in their probabilistic analyses (an important feature of their report that speaks to the author's rigor), where they show that for a population with a 1% expected prevalence of OAG, the Tech and GO strategies will not be cost-effective 80-90% of the time. For a population with a 5% expected prevalence (a level seen only among the very old, or high risk ethnic groups), the Tech strategy will be the cost-effective strategy over 50% of the time, only if the screening interval is set at five to ten years.