A Simple Metric Can Be a Powerful Tool for Planning and Advocacy

Abstract

A little more than a decade ago, Foster^1,2 provided a simple metric for estimating the number of cataract operations required to prevent needless blindness and vision impairment from cataract in any given population, the cataract surgical rate (CSR): the number of cataract operations needed to be performed per million population per year. This was both prescient and practical; the CSRs of wealthy countries, presumably meeting the eye care demands of their relatively well-served populations, currently hover around 5000 to 6000, while those of most poor and middle-income countries are substantially lower (200-2000). This simple but elegant metric brought immediate attention to the vast chasm between the CSRs in countries where the population could demand and receive cataract services deemed appropriate for optimal visual functioning and quality of life and the CSRs of those that could not.