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Reading Comprehension of Adults

by Irving Lorge & Raphael Blau - 1941

A discussion regarding the reading comprehension of adults. Advertisers, publishers, and educators of adults can prepare material at levels corresponding to the reading level of the average thirteen- or fourteen-year level with the expectation that more than two-thirds of adult readers will comprehend it.

Authors and publishers, editors and advertisers, textbook writers, and teachers have been concerned with the development of books, magazines, advertisements, and teaching materials that will be readable by adults—readable in the sense that the printed page will be comprehended and understood so that the ideas will be disseminated, the articles purchased, and the lessons learned. In the practical world of today, the people concerned with communication of ideas have developed a rough-and-ready concept of the "average reader" as one who can understand printed material on the sixth-grade level or as one who can comprehend the kind of printed material that an average twelve-year-old readily understands.1

The conscious or unconscious adoption of the crude standard of sixth-grade or twelfth-year level is based on the felt need for some practical gauge for preparing printed materials. Such a standard is not altogether accidental. Out of the facts and fancies about the adult, the sixth-grade standard developed. The facts concern the intelligence level of the adult population. From World War I came the widely popularized generalization that the intelligence of the white draft was not much above the thirteen-year level. The accumulated evidence about the intelligence of adults indicates that such a quantitative determination was not incorrect. The fancy, however, is concerned with mental decline and with the interpretation of mental tests of adults. Mental decline was argued by analogy from the data concerning the loss of visual acuity with age, the loss of auditory acuity with age, the slowing of reactions with age, and so on. It has been demonstrated, however, that the power to deal with intellectual tasks does not decline with increasing age. In general, the power to handle intellectual problems reaches maximum somewhere between ages sixteen and twenty-four, and thereafter remains relatively unchanged throughout life. Of course, if a time-limited mental test is used for estimating intellectual level, the scores in successively older age groups will diminish, but such reduction in score is primarily a function of declining reaction speed and not of absolute intellectual power.2

Of course it is relatively easy to administer tests of reading ability to determine the reading level of children in school or of children of school age. It is much more difficult to get adults to take tests so as to make an adequate estimate of their reading skill, level, or attainment. Only by fortuitous circumstances is it possible to give tests to large samples of adults to obtain some indication of their reading competence. Two such opportunities presented themselves in the last five years.


In December, 1938, and January, 1939, a population of 242 adults in the age range from 20 to 70 years were given a series of intelligence, reading, and achievement tests. These adults were made available through the Works Progress Administration. On the basis of this group, it was possible to calibrate reading tests in terms of school population norms. From this group, who took four forms of the Thorndike-McCall Reading Scale, two forms of the Reading Test of the Thorndike Intelligence Examination for High School Graduates, two forms of the Gates Reading Survey for Grades 3-10, and the Traxler Silent Reading Test, and other tests, it was possible to make reliable and valid estimates of reading comprehension ability of a sample of the adult population. It is interesting to note that the average reading level of this sample is approximately at grade 9.2 at age 15.1, with the middle two-thirds showing reading comprehension between that of grades 6.8 and 14.6, or for school ages between 13.2 and 17.7. Only a sixth of this group showed comprehension level below that of the average seventh grader. More important, however, was the fact that from the Part III Reading Test of the Thorndike Intelligence Examination, valid estimates of reading grades could be made at or near age 34.


The study of the WPA adults, however, left much to be desired. It was not known what kind of sample of the general adult population they were. Fortunately, it was possible to test a group of adults whose ability in reading comprehension was known at the time they were in school in the eighth grade at about age fourteen.

The second sample of adults were individuals who had been tested in the eighth grade of New York City public schools in 1921 and 1922. Between December, 1921, and November, 1922, over two thousand children were tested with tests of reading, arithmetic ability, clerical aptitude, and mechanical adroitness. These tests were administered as prognostic instruments in connection with a study of vocational success in relation to abilities shown at or near age fourteen. Of this sample, 862 were boys in the second term of the eighth grade of elementary schools in Manhattan—a fairly representative sample of boys in grade 8B in New York City in 1921-1922.3

At the 1921-1922 testing, each boy was given under standard conditions each of the following tests: Thomdike-McCall Reading Scale; I.E.R. Arithmetic; Stenquist Assembly Test; I.E.R. General Clerical Test(C-1).

From 1921-1922, these individuals were followed up in order to obtain their work career records. In general, every boy was seen at least once every other year. Over a period of twenty years, the staff managed to keep in touch with more than five hundred of these individuals.4

In November and December, 1932, and in March, 1933, the boys were asked to return to Teachers College for reexamination with the same tests they had taken in 1921-1922. About one-fifth of the group returned to take the tests. The data for the entire group, and for the volunteer retest group are presented in Table I. On the basis of statistical tests, it was established that the volunteer retest group may be considered as a random sample of the total basic sample. The data for the retest group may then be considered as representative of the total sample, and, by extension, of New York City adults who had attained the eighth grade of elementary school.



Again in May, 1941, after twenty years of follow-up, these individuals were invited to come back to the College for testing. In this program, they were given Part III, Form V, of the Thorndike Intelligence Examination for High School Graduates, the Otis Self-Administering Test of Mental Ability, Higher Form A, on a twenty-minute time limit, the Minnesota Scale of Opinions, and a questionnaire on their activities and interests. This time 133 men volunteered. Their basic 1921-1922 data are shown in Table I. Forty-seven of the 1941 volunteers had also taken the 1932 battery of retests. The 1941 volunteers may be considered a random sample of the original total group.

From the total sample in 1921-1922, from the volunteer sample of 1932-1933, and from the volunteer sample of 1941, it is possible to estimate the reading comprehension level of an identical group of men at ages 14, 25, and 34 years. The T-score equivalents for the Thorndike-McCall Reading Scale averages at the specified ages are:

For age 14 based on 862 cases

For age 25 based on 163 cases

For age 34 based on 133 cases




In terms of the established norms, the grade equivalents for the Thorn-dike-McCall Reading Scale at the specified ages are:

For age 14

For age 25

For age 34

grade 6.8

grade 11.3

grade 9.2

And in terms of the established grade norms, the age equivalents for the Thorndike-McCall Reading Scale at the specified ages are:

For age 14

For age 25

For age 34

age 13.2

age 15.9

age 15.0

These results show that a specified group of adults who are subjected to the usual tasks and activities of post-adolescent life do, on the average, improve in their reading comprehension. Some of these post-adolescents, of course, went to school beyond their fourteenth year; others, however, failed to complete successfully the eighth grade, and went to work. All, now at age 34, are either at work or seeking work. It is significant, however, that twenty years after being in the eighth grade, these adults are reading at a significantly higher level than they did at age 14.

An interesting confirmation of these facts may be obtained by inspecting the results for the group of 47 adults who took the tests in 1921-1922, 1932-1933, and 1941.

The specified equivalents for this group are:

At age 14

At age 25

At age 34













In the special group of 47, and in all groups, the facts indicate that, on the average, there is considerable improvement in reading comprehension as a function of time over the comprehension level prevalent at age 14. There is further evidence that the recession in reading comprehension from age 25 to age 34 is relatively small. The group of adults read much better than was expected from the general concept of the "average reader."

The facts, illustrated in the data from the retest samples, are not altogether novel. K. E. Norris, in a study of adult workers, gave several reading tests to groups of employed and unemployed male adults. He assumed that adults should read as well as the average person does in the grade corresponding to the highest grade reached before leaving school. His conclusions show that such an assumption is incorrect. Norris states:5

The evidence of this investigation points to a quite general improvement among adults in the ability to understand and use the English language. Results on the New Stanford Achievement Tests . . . reveal gains in English knowledge and skills in practically all groups of men whose original schooling terminated in the elementary or early secondary school grades. . . . The general New Stanford Reading averages (vocabulary and paragraph meaning: Tests 1 and 2 combined) indicate considerable improvement on the part of men who had left school at grades VI, VII, VIII, or IX, although the grade X and grade XI groups have lost slightly in this ability.


The facts may, at first glance, seem rather startling. Groups of adults improve in the ability to comprehend materials read. Interestingly enough, in contradistinction to the facts about reading, are the facts about arithmetic skills and computation. In general, as the adult grows older, these computational skills diminish and recede. The differences in direction for arithmetic and for reading comprehension may be explained in terms of ordinary usage. The adult, in a constantly changing world, must learn to get new facts, new understandings, and new interests and attitudes. In such learning, he utilizes the arts of communication by which such knowledge can be acquiredùwhether it be print, radio, or personal conversation and instruction. Daily, adults are practicing communication successfully. In arithmetic computation, only specially employed groups get similar extensive practice.

The averages in reading comprehension, however, should be extended to a consideration of the variabilities of the specified groups. Approximately two-thirds of the adults aged 34 are equivalent in reading comprehension to the grade ranges 7.3 to 12.8. One-sixth of this group is reading less well than the average seventh grader, and one-sixth of the group is reading at age 34 better than the average high school graduate. These facts suggest that the average adult reader is comprehending written materials better than the rule-of-thumb standard adopted by authors and publishers, editors and advertisers, textbook writers and teachers.

Of course, there is a correlation between the total amount of formal education and reading comprehension score. In the retest group, an estimate of total number of years of formal schooling completed was made by giving credits for years of day school instruction, and semesters of extension, apprenticeship, and evening school work. The correlation between the measure of completed schooling and the reading comprehension score at or near age 14 was .32, and the correlation between the measure of completed schooling and the reading comprehension score at or near age 34 was .66. The reading comprehension score of an adult at age 34 can be predicted from a knowledge of the amount of formal schooling completed and the reading comprehension status at or near age 14. The multiple correlation is .76. When one recognizes that the reliability of the reading comprehension score at age 34 is of the order of .80, it is significant that reading can be predicted so well.

The nature of reading comprehension has been a topic involving considerable debate. The data from the retest groups, however, may throw some additional light on the controversy between reading as reading and reading as intelligence. The retest group also took the Otis Self-Administering Test of Mental Ability, Higher Form A, in a twenty-minute time interval. The correlation between the Otis test and the measure of reading comprehension at age 34 was .82. Considering the reliabilities of the two measures involved, it seems reasonable to state that as a first approximation, measures of intelligence predict measures of reading comprehension among adults. If the distribution of intelligence in the adult population is known, it can be used to gauge the relative level of reading comprehension.

Any reasonable interpretation of the facts suggests that adults read better than popular opinion expects. The research work on the reading of adults, until recently, has been directed toward the understanding of the nature of the reading page as stimulus, the nature of adult reading interests, the accessibility of reading for adults, and finally the making of readable books for adults. It was found that there was a significant lack of books for the non-professional adult. Professor Lyman Bryson and others, in connection with the Readability Laboratory of Teachers College, prepared a series of books for the Peoples Library6 which attempted to provide stimulating material on the level of the average reader. In the absence of knowledge of the ability of the average reader to comprehend written materials, the Laboratory accepted the rough-and-ready concept of the average reader. They developed books that were about interesting topics, presented in good format, and at a price that adults could afford.

There is always the possibility, however, that material gauged for the average reader may not contain enough ideas per book or per page read. In order to make a book readable, very frequently the quantity and quality of ideas must be somewhat attenuated. The average reader whose reading ability is of the seventh- or eighth-grade level may find it costly to read materials prepared for a reader with ability much lower than his own. Psychologically, he may become frustrated in his search for ideas or significant viewpoints when he reads without adding in any way to his stock of facts, understandings, or attitudes.

The success of a magazine such as Reader's Digest suggests that adults seek interesting articles in which the number of ideas per page is relatively large. The articles in Reader's Digest compress many ideas into a small reading unit. The reading difficulty of articles in Reader's Digest can be estimated fairly well from the Lorge Formula for estimating reading difficulty.7 Through the courtesy of Mr. Rudolf Flesch of Teachers College, estimates of the reading difficulty of seventy-five passages selected at random from five issues of Reader's Digest for 1941 were made available. The estimated average reading difficulty of these passages suggests that the articles are written at approximately the level of the average seventh-grade school child. The range in difficulty, of course, varies from about the fifth grade to beyond the ninth grade.

The conciseness of the Reader's Digest passages, their relatively great compression of ideas, and their estimated difficulty level suggest that adults seek reading materials that will yield information, interpretation, and points of view in a form that is psychologically efficient. The average level at which these articles are written indicates that about half of the articles are at a level of grade 7.4 or higher. The editors of Reader's Digest seem to have adapted their articles to a reading level which will reach most adult readers today. Five-sixths of our group retested at age 34 can comprehend reading at levels corresponding to grade 7.3 or higher.

It should be indicated, however, that the averages reported for the retest group, at age 34, represent the reading comprehension scores of persons who had succeeded in reaching the eighth grade. Some of these men went beyond the eighth grade in their formal regular and extension education. The facts about the reading comprehension of adults who left school prior to the eighth grade can be deduced from Dr. Norris' study. It seems clear that the adults in Dr. Norris' group are reading significantly better than the level expected from the highest school grade they reached before going to, or seeking, work. Any reasonable weighting of Dr. Norris' results and of our own data suggests that the average adult under 40 years of age improves in his ability to comprehend written or printed materials relatively over his comprehension at or near age 14. The generalization regarding reading comprehension is limited to adults under 40 years of age since it is known that most of the advances in teaching reading for comprehension have been made since 1915.

If persons having a maximum of six, seven, or eight grades of formal schooling read at grade 7.2 or higher, and if persons having eight or more years of schooling read at an average of grade 9.2, it seems that the reading level of persons now 20 to 40 years of age may be placed at grade 7.3 or at the reading level of the average 13½ year old. Such a level will not be unduly high, since persons reading at a level below grade 7.3 will comprehend some of the material they read even though it is pitched at a higher level. Adults, older than 40 years, will comprehend materials at these levels, although with varying degrees of understanding.

Advertisers, publishers, and educators of adults can prepare material at levels corresponding to the reading level of the average thirteen- or fourteen-year level with the expectation that more than two-thirds of adult readers will comprehend it. The data presented indicate that the reading comprehension level of adults is considerably higher than that indicated by a rule-of-thumb standard of sixth grade or twelfth year. Moreover, the attributing of a 13½ -year-reading level to the adult fails to give an accurate description of an adult's reading ability. The adult brings to the comprehension of written materials the totality of his life experience. The adult's experiences may add considerably to his grasp of ideas and to his interpretation of them. Such factors of life experience, unfortunately, are not taken into consideration in the estimation of an adult's reading level. It must be stressed that the reading comprehension of the average 13-year-old child is used primarily as a gauge. The adult comprehending at the 13½-year level or a higher level understands a quite different complex of ideas, facts, and attitudes. The average adult, with his greater experience, with his matured interests and attitudes, will comprehend materials in a way quite superior to the average 13-year-old child.

1This study was made possible by funds granted by Carnegie Corporation of New York in support of studies of the reading comprehension level of adults and of young workers in a metropolitan area. The Corporation is not, however, the author, owner, publisher, or proprietor of this report, and is not to be understood as approving by virtue of its grant any of the statements made or views expressed therein.

Acknowledgment is also gratefully extended to the Works Progress Administration, New York City, Project No. 665-97-3-6 sub 7-sub 12 (Irving Lorge, sponsor), who furnished some of the personnel who acted in the capacity of experimental subjects.

2Lorge, Irving. "The Influence of the Test upon the Nature of Mental Decline as a Function of Age." Journal of Educational Psychology, Vol. 27, pp. 100-110, February, 1936.

3Lorge, Irving. "Retests after Ten Years." Journal of Educational Psychology, Vol. 25, pp. 136-141, February, 1934.

4Thorndike, Edward L. and Others. Prediction of Vocational Success. The Commonwealth Fund, New York, 1934.

5Norris, K. E. The Three R's and the Adult Worker, pp. 127-128. McGill University, Montreal, Canada, 1940.

6Published by The Macmillan Company.

7Lorge, Irving. "Predicting Reading Difficulty of Selections for Children." Elementary English Review, Vol. 16, pp. 229-233, October, 1939. Work Sheets and Directions for the Use of the Lorge Formula for Estimating the Grade Placement of Reading Materials may be had by addressing requests directly to Professor Lorge at Teachers College.

Cite This Article as: Teachers College Record Volume 43 Number 3, 1941, p. 189-198
https://www.tcrecord.org ID Number: 9074, Date Accessed: 5/27/2022 6:21:56 PM

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