I read with interest the article by Kleinstein et al1 on the distribution of refractive error in children as a function of ethnicity. The Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study Group is to be commended for its careful attention to adequate cyclopegia, concern for reproducible measurement, and appropriate statistical analysis. In the abstract, the authors conclude that ethnicity has a significant effect on the distribution of different types of refractive errors, a statement that is supported by the data. However, the conclusion given in the text, that “[t]he high prevalence of refractive errors in children aged 5 to 14 years . . . indicates that uncorrected refractive errors are a major public health problem,” is not supported. The study was not designed to determine whether or not a given refractive error was a “problem” to the patient, let alone to the body politic. Figure 2 shows that the vast majority of children in this study were between −1 diopter (D) and +2 D spherical equivalent. Table 2 demonstrates what happens when you define hyperopia, myopia, and astigmatism as diseases: changing the definition of the normal upper limit of refractive error by 0.25 D (a clinically trivial amount that is within the order of magnitude of measurement error) has a very significant effect on the prevalence.
Brown SM. Pediatric Refractive Errors, Ethnicity, and Public Health. Arch Ophthalmol. 2005;123(1):124. doi:10.1001/archopht.123.1.124-a