75 The Economics of Myopia

The Singapore study49 on myopic schooling teenagers found a conservative median annual cost of US$83. This is slightly higher but in the same magnitude as the USA estimate. This is probably because the Lim et al. study was on a prospective cohort of myopes measuring actual expenditures. In contrast, Vitale et al. used cost data based on Centers for Medicare & Medicaid Services fee schedules for 2000, and expenditure data from the Medical Expenditure Panel Survey. Also, the amount that a private individual is willing to pay is larger than the amount the government is willing to subsidize. The difference could be equated to the extra amount private individuals are willing to pay for other factors such as design and esthetics — it is possible to get a cheap pair of spectacles in Singapore for US$35.

The burden of myopia

Table 7 shows the number of myopes, approximately 900 million, around in the world who pay for vision correction. In the US, the annual cost is approximately $US50. Since the Singapore cost estimate is higher, we used the US cost data as a conservative estimate for the cost of myopia. However, the cost in US dollars in poorer countries like India would be lower than that in the USA, so we can use purchasing power parity to estimate the cost of myopia in these countries. A pair of spectacles in USA is the same as the cost of a pair of spectacles in Russia. In real life, it is not as simple as that, but it will suffice for an approximation for the global cost of myopia. Thus the global burden of myopia would be approximately $US50 x 900 million, or $US45 billion.

Further Directions for Economic Research

A major limitation in our analysis is the paucity of cost data from large regions of the world. This necessitated the extrapolation of cost data from the USA, rather than from Singapore, as the USA cost data were more conservative. Instead of just a burden of disease study, we could perform partial and full evaluations examining the benefits of treating myopia as well as the costs, and define possible alternatives of action. The benefits of reducing myopia would include reduction of diseases which myopes are at greater risk, e.g., cataract, glaucoma and retinal detachment, and their attendant direct and indirect costs. Alternative courses of action might include government programs for free sight tests and glasses.

77 The Economics of Myopia

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Section 2

Clinical Studies and

Pathologic Myopia

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