PubMed Health⌕ Search

Biomedical subjects

A Richler

Publications and source records attributed to A Richler.

6 recordsLinked to original sources
PubMed1983

Cylindrical refractive error: a population study in western Newfoundland.

The distribution of cylindrical refractive error (right eye only) is presented for 957 persons, comprising approximately 80% of the population (aged 5 years and over) of three western Newfoundland communities. In 72% of males and 60% of females no cylindrical error was found; 12% of males and 19% of females had errors greater than 0.5 D. Cylindrical errors of 2 D or greater were found in 2.5% of females of but only 0.5% of males, affecting females of all ages but males aged less than 15 years only. Persons aged 45 years and up had fewer cylindrical errors, more against-the-rule and less with-the-rule astigmatism than persons below that age. Cylindrical error and spherical error, and in particular against-the-rule error and myopia, commonly occurred together. Among persons aged 5 to 14 years an association of with-the-rule error with nearwork is suggested.

Adolescent↗
PubMed1981

Nearwork and familial resemblances in ocular refraction: a population study in Newfoundland.

There is considerable epidemiological evidence that the nearwork associated with formal education can cause myopia. The potential for nearwork and education, as aspects of common familial environment, to inflate resemblances among nuclear family members in ocular refraction, was therefore investigated in a sample of 957 persons aged 5 years and over, comprising approximately 80% of the population above that age in three communities on the west coast of Newfoundland. Refraction was evaluated using standard optometric methods, nearwork measured in hours/day as reported by each subject, education measured as last completed school grade in years. The effects of nearwork and education on refraction resemblances were evaluated by adjusting refraction for age and sex, then comparing correlations or regressions among relatives before and after further linear regression adjustment of refraction for nearwork and education. Reductions in sib-sib correlations and offspring-parent regressions were achieved in this way, suggesting that these environmental factors inflate familial resemblances in refraction. Patterns of resemblances among relatives after adjustment suggest that the effects of nearwork and education on refraction resemblances were not completely removed by the linear regression adjustment used.

Adolescent↗
PubMed1980

The distribution of refraction in three isolated communities in Western Newfoundland.

Data were collected on refraction in three isolated communities in western Newfoundland. Altogether 971 persons, about 80% of the population, were refracted. Subjects were not visually selected. Females showed a greater range of refractions than males at most ages, generally had more negative refractions than males, in particular at younger ages, and showed negative age group means earlier than males. Persons under 30 had more negative mean refractions, and more formal education than persons over 30. The age distribution of refraction in this population is compared with that reported by several others, and arguments presented that exposure to formal education is associated with increased myopia.

Adolescent↗
PubMed1980

Refraction, nearwork and education. A population study in Newfoundland.

There is little information directly relating ocular refraction and nearwork habits in representative human populations. Ocular refraction (diopters), nearwork (hours per day), and education (years) were therefore measured for 957 persons comprising 80% of the population aged 5 years and above of 3 communities in western Newfoundland. Refraction was moderately, consistently and significantly correlated with nearwork from ages 5 to 60, and remained so after adjustments for the association of refraction and nearwork levels with age, sex and education. Multiple regression coefficients relating refraction to nearwork decreased from -0.43 D/h at ages 5-14 years to -0.22 D/h at ages 60 years and up. The magnitude of this association, and its consistency and persistence over a wide age range, suggest that large amounts of nearwork in childhood may contribute to the prevalence of clinical myopia.

Adolescent↗