The relationship between hypothyroidism and reading retardation was investigated among selected elementary school children for the purpose of contributing to data regarding the medical aspects of dyslexia in order to stimulate the interest of school health personnel. The experimental method was used to explore the hypothesis that a significant relationship exists between reading retardation and hypothyroidism.

Sixty-four underachievers in reading enrolled in one elementary school were selected for study. Physical examinations, laboratory tests, and individual psychometric measures were used to evaluate the physical and academic status of each of the study subjects. A diagnosis of hypothyroidism was made among the study subjects by an endocrinologist.

Matched according to intelligence and chronological age, fifty-seven subjects wore divided into two control groups and one experimental group. Individual measures of reading grade placement were made at the beginning of the study period and repeated at the end of a three-month interval.

Children in one control group were given no special treatment or medication during the study period so that the change in reading achievement that would be expected among all study subjects could be observed. Children in a second control group were given a thyroid placebo during the same three-month interval to estimate the possible psychological effect of taking medication on the subjects' reading achievement. Hypothyroidism was present among the nineteen children in the experimental group. These children were medicated with thyroid extract for the duration of the study period, to observe the effect of the medication on the reading achievement of these subject.

The gains in reading achievement of fifty-four subjects were compared to analyze the significance of the reading gains in the medicated group. The findings indicated that a relationship between hypothyroidism and reading retardation existed among the subjects studied at the seventy-sixth per cent level of confidence. Recommendations were made to explore this trend further, using a larger study sample and a longer study period.

A correlation between bone-age delay and academic retardation seemed apparent among the children studied. Confirmation of this premise would serve to augment the purpose of the present study—to contribute to medical data concerning reading disability in elementary school children.

LLU Discipline





Graduate School

First Advisor

Betty Trubey

Second Advisor

Winifred Edwards

Third Advisor

Willis King

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Hypothyroidism; Reading



Page Count

vii; 196

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website



Loma Linda University. Del E. Webb Memorial Library. University Archives