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A comparison of 140 male myopes and 118 male nonmyopes of the entering class of Virginia Military Institute cadets in 1968 demonstrated that there are a number of Strong Vocational Interest Inventory test items which will clearly differentiate myopes from nonmyopes so that it is possible to identify 76% of the individuals falling into either class on the basis of a stepwise discriminant analysis based almost entirely on the Strong Vocational Interest Blank. The items which discriminate in favor of the myopes are essentially those which require academic achievement and individual creative performance, whereas the items which are in favor of the nonmyopes are those which require business and selling skills as well as outdoor types of activities. Further, the myopes are significantly more likely to achieve officer status and win more academic awards than the nonmyopes.

Studies dealing with the development of myopia in primates are considered as they contribute to our understanding of myopia. Myopia appears to develop in two stages. The first is a lenticular change in eyes which have been focused at nearpoint for long periods; the lens remains continuously accommodated. Since accommodation in monkeys results in an increase in vitreous chamber pressure, a comparable increase in children could induce the second stage--an increase in the size of the vitreous chamber and a corresponding increase in axial length or true myopia. Behavior and personality appear to be related to myopia.

The Houston Myopia Control Study is a 3-year randomized clinical trial in which each of 213 myopic children was placed in either a single vision (standard treatment) group, a +1.00 D add treatment group, or a +2.00 D add treatment group, on the basis of a randomized procedure. Subjects for the three treatment groups were matched on the basis of sex, age, and the initial amount of myopia. The study involves two groups of investigators: an evaluation team, whose task has been to evaluate candidates before entering the study and to reevaluate each subject on a yearly basis for the 3-year period, and a patient care team, whose task has been to prescribe glasses for each subject as well as to counsel subjects and their parents in the correct use of the glasses and to provide a follow-up examination every six months for the duration of the study. Once the glasses had been prescribed, members of the evaluation team were not permitted to know which subjects wore single vision lenses and which wore bifocals. In the interest of good patient care, members of the patient care team knew which subjects wore single vision lenses and which wore +1.00 D add or +2.00 D add bifocals. In this report, the authors discuss theories concerning the etiology of myopia, methods that have been used in an attempt to control the progression of myopia, and the design of the current study. Further reports will present the results of the study on the basis of the data collected by each of the two study teams.

Forty-three native American bifocal wearers grouped by yearly age levels from 9 to 15 with a mixed group of 6 to 8 year olds are matched on beginning age, sex, beginning refractive error and ending age with 83 Native American control subjects. Similarly 226 Caucasian bifocal wearers are matched on the same criteria against 192 control subjects. Although the comparisons are made on each age group, the average annual rate of progression for the bifocal Native American subjects is -0.12 and -0.10 diopters in the right and left eyes respectively against a comparable rate of progression of -0.38 and -0.36 diopters for the control subjects. These differences are significant but not as significant as those found on the Causcasian subjects of -0.02 and -0.03 diopters right and left eyes against -0.53 and -0.52 diopters for the controls.

Two measurements can be taken to determine the refractive error in human beings: a subjective, lens preference measurement and objective retinoscopy. This study determined the subjective refractive error in eight pigtailed monkeys by placing lenses of different powers in front of peepholes in a solid wall cage and recording the amount of time each subject used the holes. Retinoscopy measurements were then taken and compared to the subjective findings to determine the degree of similarity between these two refraction methods. The results showed a high correlation between the subjective measurements and the vertical ocular refraction (VOR) and spherical equivalent (SE) (rho = 0.96), further supporting generalizations made from nonhuman primate vision studies to human beings.

A questionnaire containing: (a) a questionnaire of physical characteristics associated with psychosomatic symptoms, (b) questions to determine the presence of myopia or hypermetropia but not the amount of error, (c) a shortened version of the Gough Adjective Check List, and (d) the Heist and Yonge Omnibus Personality Inventory were administered to 782 introductory psychology students attending Washington State University. This group consisted of 297 self-identified myopes (117 males, 180 females), 439 emmetropes (207 males, 232 females), and 46 hypermetropes (15 males, 31 females). Results indicated that myopes and nonmyopes differed from one another with respect to their value systems, personality, and physical characteristics as assessed by the components of the questionnaire. Differences in these characteristics were consistently found by all assessment techniques to exist most often between myopes and hypermetropes and between emmetropes and hypermetropes rather than between myopes and emmetropes. In general myopes exhibited a personality pattern of introversion, whereas hypermetropes maintained a pattern described as extroverted.