Biomedical subjects
D A Wissmann
Publications and source records attributed to D A Wissmann.
The epidemiology of myopia.
Many people have reduced unaided vision because of myopia, a spherical error of refraction. The biological theory of myopia views myopia as the result of genetically determined characteristics of eye tissues, whereas the use-abuse theory views myopia as the result of habitual use of the eye at a near focal length, near-work. The use-abuse theory implies that myopia is preventable whereas the biological theory does not. Myopia varies over age, gender, race, ethnicity, level of education, social class and degree of urbanization. The explanation of the epidemiology of myopia in the use-abuse theory is that some types of people do more near-work than others. Using data from the Health Examination Survey of 12 to 17-year-olds conducted by the US Public Health Service from 1966--1970, this paper finds that the use-abuse theory can explain at least some of the variance of myopia and much of the socially patterned variance. This finding raises the possibility that at least some of the myopia extant in a population is preventable.
A statistical analysis of the Biological Theory of spherical error of refraction.
It is widely believed that Adolph Steiger proved in Die Entstehung der sphärischen Refraktionen des menschlichen Auges (The Origin of Spherical Refractions of the Human Eye) that the Biological Theory of spherical error of refraction statistically explains the entire distribution of such errors, hence excluding other theories such as the Use-Abuse Theory. Although Steiger's Biological Theory is a statistical argument, he never put it into formal notation. This paper puts a modernized version of the Biological Theory into formal statistical notation. It shows that the Biological Theory explains the dispersion of distributions of spherical error of refraction but not the location of their means. The Use-Abuse Theory is an explanation of mean spherical error in populations. Since a complete theory of spherical errors of refraction needs to explain both the mean and the dispersion of their distribution, the two theories are potentially complementary. No empirical evidence, however, is presented here for either theory.
Age, reading, and myopia.
This paper tests whether the use-abuse theory or the biological theory of myopia explains the appearance and progression of myopia among 12--17 year olds in the United States. The use-abuse theory predicts that current amount of reading and cumulative exposure to reading, as indicated by years of schooling, explain myopia. The biological theory predicts that either age from birth or age from puberty explains any tendency for myopia to appear and progress among children or adolescents. Regression analysis shows that education explains all the tendency for myopia to appear and progress among 12--17-years-olds. When we control for education, age is not related to increased myopia. Myopia progresses, on the average, 0.22 D per academic year. However, education explains only a small fraction of the variance in myopia.