Myopia Prevalence and Progression (1989) / Chapter Skim
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Appendix B: Review of the Prevalence Literature
Appendix B: Review of the Prevalence Literature
Pages 45-61
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From page 45... ...
If two of these are known or can be reasonably assumed, and if sampling is valid, then inferences about the third can usually be maple from cross-sectional data. Age patterns of myopia prevalence seem to be used in two major areas of inquiry.
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From page 46... ...
Goldschmidt (1968) studied Danish schoolchildren ages 13 to 14 and found that 9.7 percent had either a previously ascertained myopia, reduced visual acuity, or a school record of use of glasses accompanied by optimum vision achieved by spherical concave lenses in one or both eyes.
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From page 47... ...
There was no significant difference between the sexes in the occurrence of reacquired myopia," defined as poor distant vision, satisfactory near vision, ant] a deterioration of two lines in distant visual acuity in children between ages 7 and 11.
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From page 48... ...
48 TERRITORY OF HAWAII DIAGNOSIS PERCENT 30 25 20 15 10 5 0 30 25 20 15 10 5 0 PERCENT ALL RACES 100,377 HAWAIIAN 2,758 PART HAWAIIAN 2O,375 PORTUGUESE 6,562 PUERTO RICAN 1,764 SPANISH 193 OTHER CAUCASIAN 5,353 CHINESE 5,621 JAPANESE 41,684 KOREAN 1,036 FRENCH 9,732 OTHERS 5,299 FIGURE B-1 Myopic errors by race. This figure represents eyes; in many individuals both eyes have the same defect, so the percentage on a case basis would be somewhat more than half of the figures given here.
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From page 49... ...
There is, of course, concern that university students who register at the university health service may not be representative of the general student population and, furthermore, that prevalence of myopia in university students is likely to be higher than in the general population. Taken together, these studies do not seem to provide strong evidence supporting the belief that myopia prevalence is unusually high among Jews.
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From page 50... ...
studied visual acuity and the Attribution of refractive errors in 161 Australian aborigines in eight communities and 152 Australians of European origin, 20 to 30 years of age. Approximately 4.8 percent of the aborigines had a negative refractive error greater than -0.75 D., compared with 13.5 percent of the Europeans; no aborigine had myopia of greater than -4.00 D
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From page 51... ...
The criteria for myopia included a previously ascertained myopia or reduced visual acuity-or a school record of the use of glasses and, in addition, an examination in which the optimal visual acuity was achieved by use of spherical concave lenses in one or both eyes. By these criteria, 9.7 percent of students attending normal schools were found to be myopic.
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From page 52... ...
Upon excluding negative refractive errors of -1.5 D or less, the prevalence of myopia among the 1964 recruits was 9.2 percent, and after stratification by occupational category, even this small difference disappeared.
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From page 53... ...
The distributions of visual acuity based on the Snellen eye chart were similar for all three groups. The paper presents extensive, detailed distributions, usually of the right eye alone or the right and left eye separately, of various measures, including visual acuity with and without cycloplegia, refractive errors in the vertical and horizontal axes, and astigmatism, using various criteria for classification.
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From page 54... ...
the subject's own corrective lens having a negative spherical equivalent, (2) uncorrected visual acuity less than 20/20 and improved by a negative sphere trial lens, and; (3)
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From page 55... ...
no (48%) visual acuity assessment, uncorrected <20/50 >20/50 no further information nutritional detailed examines examines (1 9%)
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From page 56... ...
Furthermore, in their article on myopia and corrective lenses, Angle and Wissmann (1980a) state, "Cycle Ill of the Health Examination Survey showed that 23.6% of eyes free of a problem that cannot be corrected by lenses have a corrective lens with a negative spherical equivalent correction for myopia." Whether these discrepancies are due to criteria of classification, methods of classification, the use of a subset of the data, or some other factor is not clear.
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From page 57... ...
By age 40 it had fallen below 20 percent and by 50 to about 10 percent. The authors compared the age curves for the prevalence of myopia in populations with the recent introduction of public education to those in which there had been public education for a long time, the latter showing a much more gradual decrease in myopia prevalence with age (Figure ~3~.
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From page 58... ...
used grade in school, reading test scores, and reported time spent reading magazines, books, and newspapers in a typical day as measures of near work and reading. All three were positively associated with myopia prevalence.
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From page 59... ...
studied nearly 6,000 California schoolchildren and found no difference in academic achievements between children with sufficiently defective vision to notify their parents and a random sample of children with normal vision. Since reduced visual acuity alone is an inadequate indicator of myopia, the results of the study are essentially uninformative.
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From page 60... ...
Height and Weight Several investigators (Johansen, 1950; Pendse and Bhave, 1951; Krause et al., 1982) report an association of greater myopia prevalence or negative refractive error with height and weight in children.
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From page 61... ...
This study is analogous to early dental caries research and, like dental caries, malignant myopia was found to be inversely related to annual hours of sunshine, distance to the seacoast, and fluoride and calcium levels. The author also mentions his clinical impression that myopic patients have more dental defects.
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