MENTAL ABILITY AND ITS RELATION TO PHYSICAL HEALTH AND SOCIAL ECONOMIC STATUS By J. B. Maller Institute of School Experimentation, Teachers College, Columbia
University
to study the relationship defects among the physical ability of New York City, schools of the various pupils elementary public and the relationship between these factors and the social economic status of the neighborhoods where the respective schools are lo-
The purpose of this
between mental
investigation
was
and certain
cated. Sources of Data. During the year 1932, all the fifth grade of the New York public schools were examined with a bat-
pupils
tery of intelligence tests, including the National Intelligence Test and the Pintner
Survey Test. This educationally homogeneous tested under the auspices of the Board of Education, ingroup, cluded some 100,098 pupils enrolled in 579 schools. The records of achievement and progress were also obtained for each of the public During the same year the pupils of Grade I of all schools
schools.
given health examinations under the auspices of the Department of Health. These included examinations of eyes, ears, were
teeth,
nose,
throat, heart, nutrition,
etc.
The Distribution of Intelligence. In view of the fact that these 100,098 fifth grade pupils represent a cross section of the total population of the city, the distribution of their scores (I.Q.'s) is of considerable interest. It is particularly interesting to compare it with other distributions. Figure 1 presents a comparison between our
distribution and the distribution of I.Q.'s presented by Terman. The latter is based on the scores of 905 unselected children from schools in California.1 Both distributions are in terms of per-
centages. from Figure 1 that the two distributions differ distribution is leptocurtic, peaked in the Terman's considerably. is platocurtic, relatively flat at the our while distribution center, center. In the former there are about twice as many pupils with It will be
i
L. M.
seen
Terman,
Mifflin, 1916, chap.
The measurement of
V. 101
intelligence,
New
York, Houghton
THE PSYCHOLOGICAL CLINIC
102
I.Q.'s between 90 and 110 while in the latter there ingly greater proportion of eases at the extremes.
is
a
correspond-
The differences
due to the difference in the nature of the test and the population tested. Variability of Intelligence. How do the schools of the city
are
vary with
regard
to the average
intelligence
of their
pupils?
The
'CAUFO!?riiA Data "NewYork Data
-2V1--
?
i i
_l2l_
.
Sptt TTfT
a-nd
?
Fig. 1.
8H5
U-65
%-lo5
lot-US
llb-125
2.3 ?'
La
WilriWM bOf f a
!ntrljc?ence -Quotients
The distribution of
intelligence: comparison
between New York and
California data
distribution of the averages of the respective schools and neighborwere computed for each measure. Figure 2 shows the dis-
hoods
tribution of intelligence
scores
(I.Q.'s)
of
100,098
fifth
grade pupils.
It also shows the distribution of the averages of the 579 schools and the averages of some 300 health areas, into which the city is divided.
MENTAL ABILITY AND RELATION TO HEALTH
103
seen from Figure 2 that the distribution of scores from 50 to 160 with a mean of 100.2 and an S.D. of 20.9 ranged and that the respective public schools vary enormously with regard to average intelligence. The means ranged from 70 to 122 with an average of 100.0 and an S.D. of 9.4. The means of neighborhoods ranged from 79 to 120 with a mean of 100.5 and an S.D.
It will be
Individuals, N-100,098. Schools, N-579. Neighborhoods, N-300. Fig. 2.
of 8.2.
The The distribution distribution of of
and intelligence: neighborhoods individuals, schools, schools, and neighborhoods intelligence: individuals,
heterogeneity or intra-school homogeneity intelligence) may be expressed in terms of the the sigma of the means to the sigma of the total
This inter-school
(with regard
to
ratio between In
population.
our
hoods tion.2
are
in
no
this correlation ratio is .45 ? .02. For correlation ratio is .40 ? .03. It seems schools as well as the respective neighbor-
case
neighborhoods this then that the respective the
sense
random
samples
of the total school
popula-
2 See J. B. Mailer, Economic and social correlatives of school progress in New York City, Teach. Coll. Bee., 1933, 34, 655-670.
104
THE PSYCHOLOGICAL CLINIC
Health Measures. A summary of the results of health examinations is shown in Table 1. This is based on the examination of 140,230 pupils of Grade I and Kindergarten of all New York City schools (including both public and parochial schools). Table 1
presents the incidence of defects
It reads as folper 1000 cases. lows: Of each 1000 children examined in Manhattan, 239 were found free from all defects, 91 were found to have visual defect, 496 had carious teeth, etc. Table 1 Incidence
op
Physical Defects
Pupils Schools
among
op
Grade I, New York City
(per 1000 children inspected) Free from all
Location
Defects
Manhattan Bronx
239 367 348 374 457
Brooklyn
Queens
Richmond
Total, city Average of neighborhoods S.D. of neighborhoods
Variation
of
Visual De-
fects
Mouth Nasal Ton- Heart OrDeObstructhoHysils Teeth giene tion fect pedic Carious
91 83 85
496 338 434
52
324
7 41
237 157
373 277 256
31
418
13
130
261
357 425
33
28
168
335
48 74
32
200
283
10 22
330
77
426
35
209
291
23
87
51
93
43
97
79
Health Measures.
among the schools with
for the city
regard
Striking
20 35
19 23
Nervous
Disturb.
Malnutri-
tion
5 12
294 211
7
5
183
10 1
126
13
5 1 6
199
14
6
201
9
4
81
18 27
variation
was
41
found
to the various measures of health.
whole, 34 defects, but
per cent of the pupils were found the indices of the schools ranged from 8 per cent to 71 per cent free from all defects. Similarly, the incidence of visual defects for the school population is 7 per cent,
Thus,
as a
to be free from all
but in the schools it ranged from 1 per cent to 22 per cent. In malnutrition the incidence was 20 per cent for the total of the school population, while in the schools it ranged from 4 per cent to 72 per cent. The eta, expressing the relationship between the composite of health and location, was .29 ? .03. It was shown above that for intelligence the correlation ratio was .45 ? .02. Ap-
measure
parently the pupils of a given school in New York City
slightly homogeneous regard to intelligence to aspects of health, and, conversely, there is greater variability among schools in respect to intelligence than in respect to health. more
with
are
than with regard
MENTAL ABILITY AND RELATION TO HEALTH
105
Correlation. The records of health were available by schools, for each of the 579 elementary schools. The correlation between average intelligence score and the percentage of pupils having no physical defect was .5085 ? 0.2. For the respective measures of health the correlations I.Q. I.Q. I.Q. I.Q.
and and and and
were as
follows: ?.3991 ? .02 ?.4977 ? .02 ?.2643 ? .03 ?.2792 ? .03
visual defect teeth defect tonsils malnutrition
The average correlation between I.Q. and these incidences of was ?.3601. The average inter-correlation among the measures of health was .5106. Apparently measures of different of correlate health slightly higher with one anaspects physical other than they correlate with mental ability. The relationship defect
large number of 34 per cent while defect. fully Thus, having of the children were free from all defects, among the remaining 66 per cent the incidence was a little more than 2.0 defects per child. Data Concerning Neighborhoods. It is obvious that the corre-
among measures of health is also evidenced in the cases
more
than
one
lation between average intelligence and index of health is partly due to the marked differences in the nature of the population residing in the various neighborhoods where the respective schools are located. As was stated above, New York City is divided into some 300 health areas or neighborhoods with about 2 elementary schools per
neighborhood.
Federal and
municipal
statistics
are
computed by these neighborhoods.3 Various data were available for each neighborhood, including the above measures of health, vital indices
(birth rate and death rate), rate of juvenile delinquency, and economic status based on values of homes and rentals. The average I.Q. of all fifth grade pupils residing in each neighborhood was computed (Fig. 1). These averages were then correlated with the above tween average sented :
neighborhood
intelligence and
factors. The correlations beof these factors will be pre-
some
Death rate Infant mortality rate Juvenile delinquency rate Birth rate Economic status (Federal census figures of value of home
?.4266 ?.5125 ?.5681 ?.3409
=fc .03 ? .03
?.03 ? .04
rentals) +.5006 ? .03 Health and intelligence, economic status constant ? .04 +-28 s A more detailed presentation of these neighborhood factors is presented by the writer in Vital indices and their relation to psychological and social factors,
Human
Biol., 1933, 5,
94-121.
106
THE PSYCHOLOGICAL CLINIC The correlations indicate that mental
tively status. as
ability
with desirable characteristics such It correlates
negatively with delinquency.
as
is correlated
posi-
health and economic
all undesirable characteristics
and
high mortality Factor Analysis.
The present considerations dealt primarily ability and other factors. The
with the correlation between mental
limited space will not permit the presentation of the various intercorrelations among the 14 other variables (measures of health, social economic status and vital indices). Only one aspect of the presented. The tetrad difference analysis was applied to the table of 105 intercorrelations. There were a intercorrelations will be
number of large and significant tetrad presence of group factors.
differences, indicating
After the elimination of those correlations which curvelinear
(e.g., birth rate) the into four composites.
the
definitely combined or remaining (1) Intellect, including scores oil were
ones were
"pooled" intelligence, achievement and rate of school progress. (2) Health, including the inverted rates of physical defects, disease, and mortality. (3) Character, or social adjustment, including the inverted rate of juvenile court arraignment, delinquency, and truancy. (4) Economic status, including occupational level, home value and rental. The resulting tetrad differences were rather the small, largest one being less than three times its probable error (average correlation, .38; largest tetrad difference, .05; probable error, .02). This indicates that the four groups of measures may be considered as having one factor common to them. This common factor may be looked upon as the developmental status of the group or neighborhood which expresses itself in the level of physical, intellectual and social adjustment. tests of
Summary The populations of different schools of New York City were found to vary enormously in regard to measures of mental ability and physical health. Similar variability was found among the with regard to vital indices and social economic measures. The respective schools or neighborhoods are in no sense random samples of the total city. The implication for
neighborhoods
studies
of the
frequently
city
conducted in
one
school
or
neighborhood
is
obvious. Mental
ability
was
found to correlate
positively
with
measures
MENTAL ABILITY AND RELATION TO HEALTH
107
of health and with index of social economic status. Even when social economic status is held constant, the correlation between intelligence and health remains significantly positive. Mental ability was found to correlate negatively with death rate, infant mortality,
juvenile delinquency, and birth rate. An analysis of intercorrelations revealed of
a
factor
common to measures
vocational and social
of intellect,
adjustment.
the possible presence physical vitality, and
University
to study the relationship defects among the physical ability of New York City, schools of the various pupils elementary public and the relationship between these factors and the social economic status of the neighborhoods where the respective schools are lo-
The purpose of this
between mental
investigation
was
and certain
cated. Sources of Data. During the year 1932, all the fifth grade of the New York public schools were examined with a bat-
pupils
tery of intelligence tests, including the National Intelligence Test and the Pintner
Survey Test. This educationally homogeneous tested under the auspices of the Board of Education, ingroup, cluded some 100,098 pupils enrolled in 579 schools. The records of achievement and progress were also obtained for each of the public During the same year the pupils of Grade I of all schools
schools.
given health examinations under the auspices of the Department of Health. These included examinations of eyes, ears, were
teeth,
nose,
throat, heart, nutrition,
etc.
The Distribution of Intelligence. In view of the fact that these 100,098 fifth grade pupils represent a cross section of the total population of the city, the distribution of their scores (I.Q.'s) is of considerable interest. It is particularly interesting to compare it with other distributions. Figure 1 presents a comparison between our
distribution and the distribution of I.Q.'s presented by Terman. The latter is based on the scores of 905 unselected children from schools in California.1 Both distributions are in terms of per-
centages. from Figure 1 that the two distributions differ distribution is leptocurtic, peaked in the Terman's considerably. is platocurtic, relatively flat at the our while distribution center, center. In the former there are about twice as many pupils with It will be
i
L. M.
seen
Terman,
Mifflin, 1916, chap.
The measurement of
V. 101
intelligence,
New
York, Houghton
THE PSYCHOLOGICAL CLINIC
102
I.Q.'s between 90 and 110 while in the latter there ingly greater proportion of eases at the extremes.
is
a
correspond-
The differences
due to the difference in the nature of the test and the population tested. Variability of Intelligence. How do the schools of the city
are
vary with
regard
to the average
intelligence
of their
pupils?
The
'CAUFO!?riiA Data "NewYork Data
-2V1--
?
i i
_l2l_
.
Sptt TTfT
a-nd
?
Fig. 1.
8H5
U-65
%-lo5
lot-US
llb-125
2.3 ?'
La
WilriWM bOf f a
!ntrljc?ence -Quotients
The distribution of
intelligence: comparison
between New York and
California data
distribution of the averages of the respective schools and neighborwere computed for each measure. Figure 2 shows the dis-
hoods
tribution of intelligence
scores
(I.Q.'s)
of
100,098
fifth
grade pupils.
It also shows the distribution of the averages of the 579 schools and the averages of some 300 health areas, into which the city is divided.
MENTAL ABILITY AND RELATION TO HEALTH
103
seen from Figure 2 that the distribution of scores from 50 to 160 with a mean of 100.2 and an S.D. of 20.9 ranged and that the respective public schools vary enormously with regard to average intelligence. The means ranged from 70 to 122 with an average of 100.0 and an S.D. of 9.4. The means of neighborhoods ranged from 79 to 120 with a mean of 100.5 and an S.D.
It will be
Individuals, N-100,098. Schools, N-579. Neighborhoods, N-300. Fig. 2.
of 8.2.
The The distribution distribution of of
and intelligence: neighborhoods individuals, schools, schools, and neighborhoods intelligence: individuals,
heterogeneity or intra-school homogeneity intelligence) may be expressed in terms of the the sigma of the means to the sigma of the total
This inter-school
(with regard
to
ratio between In
population.
our
hoods tion.2
are
in
no
this correlation ratio is .45 ? .02. For correlation ratio is .40 ? .03. It seems schools as well as the respective neighbor-
case
neighborhoods this then that the respective the
sense
random
samples
of the total school
popula-
2 See J. B. Mailer, Economic and social correlatives of school progress in New York City, Teach. Coll. Bee., 1933, 34, 655-670.
104
THE PSYCHOLOGICAL CLINIC
Health Measures. A summary of the results of health examinations is shown in Table 1. This is based on the examination of 140,230 pupils of Grade I and Kindergarten of all New York City schools (including both public and parochial schools). Table 1
presents the incidence of defects
It reads as folper 1000 cases. lows: Of each 1000 children examined in Manhattan, 239 were found free from all defects, 91 were found to have visual defect, 496 had carious teeth, etc. Table 1 Incidence
op
Physical Defects
Pupils Schools
among
op
Grade I, New York City
(per 1000 children inspected) Free from all
Location
Defects
Manhattan Bronx
239 367 348 374 457
Brooklyn
Queens
Richmond
Total, city Average of neighborhoods S.D. of neighborhoods
Variation
of
Visual De-
fects
Mouth Nasal Ton- Heart OrDeObstructhoHysils Teeth giene tion fect pedic Carious
91 83 85
496 338 434
52
324
7 41
237 157
373 277 256
31
418
13
130
261
357 425
33
28
168
335
48 74
32
200
283
10 22
330
77
426
35
209
291
23
87
51
93
43
97
79
Health Measures.
among the schools with
for the city
regard
Striking
20 35
19 23
Nervous
Disturb.
Malnutri-
tion
5 12
294 211
7
5
183
10 1
126
13
5 1 6
199
14
6
201
9
4
81
18 27
variation
was
41
found
to the various measures of health.
whole, 34 defects, but
per cent of the pupils were found the indices of the schools ranged from 8 per cent to 71 per cent free from all defects. Similarly, the incidence of visual defects for the school population is 7 per cent,
Thus,
as a
to be free from all
but in the schools it ranged from 1 per cent to 22 per cent. In malnutrition the incidence was 20 per cent for the total of the school population, while in the schools it ranged from 4 per cent to 72 per cent. The eta, expressing the relationship between the composite of health and location, was .29 ? .03. It was shown above that for intelligence the correlation ratio was .45 ? .02. Ap-
measure
parently the pupils of a given school in New York City
slightly homogeneous regard to intelligence to aspects of health, and, conversely, there is greater variability among schools in respect to intelligence than in respect to health. more
with
are
than with regard
MENTAL ABILITY AND RELATION TO HEALTH
105
Correlation. The records of health were available by schools, for each of the 579 elementary schools. The correlation between average intelligence score and the percentage of pupils having no physical defect was .5085 ? 0.2. For the respective measures of health the correlations I.Q. I.Q. I.Q. I.Q.
and and and and
were as
follows: ?.3991 ? .02 ?.4977 ? .02 ?.2643 ? .03 ?.2792 ? .03
visual defect teeth defect tonsils malnutrition
The average correlation between I.Q. and these incidences of was ?.3601. The average inter-correlation among the measures of health was .5106. Apparently measures of different of correlate health slightly higher with one anaspects physical other than they correlate with mental ability. The relationship defect
large number of 34 per cent while defect. fully Thus, having of the children were free from all defects, among the remaining 66 per cent the incidence was a little more than 2.0 defects per child. Data Concerning Neighborhoods. It is obvious that the corre-
among measures of health is also evidenced in the cases
more
than
one
lation between average intelligence and index of health is partly due to the marked differences in the nature of the population residing in the various neighborhoods where the respective schools are located. As was stated above, New York City is divided into some 300 health areas or neighborhoods with about 2 elementary schools per
neighborhood.
Federal and
municipal
statistics
are
computed by these neighborhoods.3 Various data were available for each neighborhood, including the above measures of health, vital indices
(birth rate and death rate), rate of juvenile delinquency, and economic status based on values of homes and rentals. The average I.Q. of all fifth grade pupils residing in each neighborhood was computed (Fig. 1). These averages were then correlated with the above tween average sented :
neighborhood
intelligence and
factors. The correlations beof these factors will be pre-
some
Death rate Infant mortality rate Juvenile delinquency rate Birth rate Economic status (Federal census figures of value of home
?.4266 ?.5125 ?.5681 ?.3409
=fc .03 ? .03
?.03 ? .04
rentals) +.5006 ? .03 Health and intelligence, economic status constant ? .04 +-28 s A more detailed presentation of these neighborhood factors is presented by the writer in Vital indices and their relation to psychological and social factors,
Human
Biol., 1933, 5,
94-121.
106
THE PSYCHOLOGICAL CLINIC The correlations indicate that mental
tively status. as
ability
with desirable characteristics such It correlates
negatively with delinquency.
as
is correlated
posi-
health and economic
all undesirable characteristics
and
high mortality Factor Analysis.
The present considerations dealt primarily ability and other factors. The
with the correlation between mental
limited space will not permit the presentation of the various intercorrelations among the 14 other variables (measures of health, social economic status and vital indices). Only one aspect of the presented. The tetrad difference analysis was applied to the table of 105 intercorrelations. There were a intercorrelations will be
number of large and significant tetrad presence of group factors.
differences, indicating
After the elimination of those correlations which curvelinear
(e.g., birth rate) the into four composites.
the
definitely combined or remaining (1) Intellect, including scores oil were
ones were
"pooled" intelligence, achievement and rate of school progress. (2) Health, including the inverted rates of physical defects, disease, and mortality. (3) Character, or social adjustment, including the inverted rate of juvenile court arraignment, delinquency, and truancy. (4) Economic status, including occupational level, home value and rental. The resulting tetrad differences were rather the small, largest one being less than three times its probable error (average correlation, .38; largest tetrad difference, .05; probable error, .02). This indicates that the four groups of measures may be considered as having one factor common to them. This common factor may be looked upon as the developmental status of the group or neighborhood which expresses itself in the level of physical, intellectual and social adjustment. tests of
Summary The populations of different schools of New York City were found to vary enormously in regard to measures of mental ability and physical health. Similar variability was found among the with regard to vital indices and social economic measures. The respective schools or neighborhoods are in no sense random samples of the total city. The implication for
neighborhoods
studies
of the
frequently
city
conducted in
one
school
or
neighborhood
is
obvious. Mental
ability
was
found to correlate
positively
with
measures
MENTAL ABILITY AND RELATION TO HEALTH
107
of health and with index of social economic status. Even when social economic status is held constant, the correlation between intelligence and health remains significantly positive. Mental ability was found to correlate negatively with death rate, infant mortality,
juvenile delinquency, and birth rate. An analysis of intercorrelations revealed of
a
factor
common to measures
vocational and social
of intellect,
adjustment.
the possible presence physical vitality, and
