THE RELATION OF GENERAL INTELLIGENCE, MOTOR ADAPTABILITY, AND MOTOR LEARNING TO SUCCESS IN DENTAL TECHNICAL COURSES By Richard S. Schultz The
Psychological Corporation, Introduction
New YorTc
City
*
Dentistry involves a marked degree of "motor" or "mechanical" skill1 as well as a broad knowledge of the Medical Sciences. In actual practice, the dentist spends the greater part of his time '' working with his hands.'' An analysis of the dental curriculum reveals that 57.4 per cent of the student's
training
involves
manipu-
lative performances.2 A statement and definition of the abilities and qualifications which are most important, and the extent to which they contribute to success in dental
training and in actual practice are the subject earlier paper by the author, published in the Psychological Clinic.3- 4 The purpose of the present paper is to present data on the relation of general intelligence, ability to solve a motor problem and to learn a motor problem, respectively, to success in Dental Techof
an
nical Courses. Subjects The investigation included 90 men, the entire second year class, in the School of Dentistry, University of Pennsylvania. The class *
The writer wishes to
acknowledge his indebtedness to Dr. Charles R. School; and to Professors Edwin B. Twitmyer, Samuel W. Fernberger, and Morris S. Viteles, Department of Psychology, of the University of Pennsylvania. 1 Paterson, D. G., Elliott, R. M., et al., Minnesota mechanical ability tests, 1930, 5-11, 136 ff. "A scale was developed and used for grading occupations according to the judged amount of mechanical ability involved." Dentistry received a rating of 4.55 S.D., and is, therefore, considered as an occupation involving a high degree of mechanical ability. 2 The Carnegie Foundation for the Advancement of Teaching, Dental Education in the U. S. and Canada, Bulletin 19, 1926. 3 This study is part of a comprehensive program of research which has been outlined by the writer. 4 Schultz, R. S., A Review on the Measurement and Description of Qualifications for Dentistry and Dental Training, Psychol. Clin., 1932, 21, 172-182. Turner,
Dean of the Dental
226
RELATION OF INTELLIGENCE TO SUCCESS
227
selected because it represented a relatively homogeneous group. These students have received intensive technical training, preparatory to undertaking practical clinical work with patients. They averaged about 22% years of age, with a range from 20 to 28 years. was
Procedure 5
Two-Story Duplicate Maze was selected as a device for obtaining a measure of the ability to solve a motor problem as well as of the ability to learn a motor problem. This apparatus has the advantage of presenting a task involving the coordination of two "hands" combined with the use of the visual, tactile, and The Miles
kinaesthetic
It consists of two identical maze patterns, senses. mounted directly above the other, on a wooden box with two The task requires the movement of a stylus through open sides. one
a
stationary visible top pattern by one hand, while at the same a pencil is moved through a screened bottom pattern by the
time
other hand.6'7 First an attempt was made to obtain a measure of the various abilities and traits that may be evoked in adaptation to a relatively novel motor situation. Problems of varying difficulty in motor
adaptation
were arranged by rotating the bottom maze, with refthe top maze, to five successive positions (0?, 180?, 90?, 180? reverse, 90? reverse). Each position was to be traced as
erence to
quickly
as
possible.
After this
adaptability task, one of the above problems (180? position) was given as a learning task. The general instructions were to learn to trace through the maze pattern as quickly as possible without error. The Psychological Examination, American Council on Educareverse
5 Miles, 10, 365-377.
W.
R.,
The
Two-story Duplicate Maze,
6 Tlie formation of habits from a visual plan is aspects of the dental student's practical learning.
J.
Exper. Psychol., 1927, of the most
important learns, in laboratory demonstrations, lectures, personal instruction in practical work, etc., must be reproduced some time later. There is only a limited opportunity to perform actual movements or operations while receiving instruction. He must, therefore, depend on memory, models, and possibly imagery. In the course in Operative Dentistry the student is trained to explore and to make minutely controlled movements in unseen or limited visual fields, with the dental mirror 7
as an
For detailed
one
Much of what he
accessory.
description of procedure and method of scoring see Schultz, E. S., The Relation of Maze Adaptability, Maze Learning, and General Intelligence, Amer. J. Psychol., 1932, 44, 249-262.
THE PSYCHOLOGICAL CLINIC
228
tion,8 was used to obtain a measure of general intelligence. administered, before any maze tests were given, as a group
It
was
exami-
nation. Results The maze
significance
of the
tests is evaluated
scores on
the
intelligence
test and the
by comparisons with rank order ratings and
in dental technical courses, on the basis of which the studivided into Best, Average, and Poor groups.9 Test scores are distributed according to this classification. The measures of success include eight technical criteria. Three
grades dents
are
were
based
order
on
rating
structors; (2)
second year technical courses: (1) a General rank ability, the average of the ratings by three inan Average Operative rank order rating, the average
of
of the ratings by two instructors in operative technics; (3) a Prosthetic Technic rank order rating, estimate of one instructor. The final per cent marks in the technical courses for the first and second years yield five additional criteria. The criteria are numbered in the tables and I. General average rank order II. Average operative rank order III.
Prosthetic rank order
IV. V.
Average technical grade second Operative grade second year
VI. VII.
figures
as
follows:
year
Prosthetic grade second year Prosthetic grade first year
VIII. Operative grade first year These data are analyzed by a
study of how well the tests discriminate the Best, Average, and Poor groups of technical ability. Coefficients of correlation are also computed to obtain an index of the degree of correspondence between test in technical courses. 1. General
Intelligence
scores
and achievement
and Achievement in Technical Courses
In Fig. 1 and Table 1 the average score on the intelligence test for the Poor group is below the average for the Best and Average 8 Thurstone, L. L., and Thurstone, T. 6., The 1929 Psychological Examination, Educ. Record, 1930, 11, 101 ff. ? Approximately 68 per cent of the cases are included in the average group, and the remaining cases are divided equally between the two other groups. This division is based on the assumption that the abilities under consideration are distributed to follow the general trend of the normal probability curve.
of
Intelligence Test Scores
fob
Best, Average,
and
Poor Groups of Achievement in Dental Technical
Courses Best
Poor
Average
Criterion
I II II I IV V VI VI I VII I
No.
Av.
Median
Range
No.
Av.
Median
Range
No.
Av.
Median
Range
13 13
197 210
189 188 185
189
57-299 57-299 57-299 57-299 57-299 57-299 57-299 57-299
14 13
183 175
168 168
195
73-271 135-271 73-271 73-271 127-271 73-273 73-271 126-260
58
15 16 15 15 19 15
200 219 196 198
15 16 15 16 20
190
191
164 174
166 166
88-298 109-242 75-299 96-234 109-243
160 181
161
96-209
17
181
168 184
88-299 88-263
196 199 184 197 190
199
172 209 199
59
59 56 58 57 51 58
192
188 196 185 188
189
188 193 192 203 186 186
SUCCESS TO INTELLIGENCE OF RELATION
Comparison
229
Table 1
THE PSYCHOLOGICAL CLINIC
230
The differences are groups, and for tlie entire group of 90 cases. most pronounced when the Poor group is compared with the Best Coefficients of correlation (Table 2) between intelligence group. test scores and achievement in technical courses are low and sta-
tistically
unreliable. ?
?
*?
?
?
?
? ~
'er+7e
I Criterion Fig. 1.
II
III
IV
Best
Atera^e P??r
~_mj_
V
VI
VII
VIII
Comparison of Average Intelligence Test Score for Best, Average, and Poor Groups of Achievement in Dental Technical Courses
intelligence test appears to have most value in differentiating general ability in technical courses, as signified by the criThe
terion?average technical grade second
year.
Table 2 Correlation of Scores in Tests with Measures of Achievement
(Criteria)
in
General Intelligence No.
85-90
.
.
II. III. IV.. V. VI.. VII. VIII. .
.
.
.
Maze
Adaptability
+.104 + .208 -.031 + .227
+.161 +.189 +.130 +.063
Maze
52-55
P.E.r
Criterion I.
Dental Technical Courses
.073 .070 .071 .068
.070 .070 .070 .071
Learning
35-37
P.E.r
.297 .289 .294 .318 .279 .279 .372 .247
.086
.086 .083 .083 .085
.084 .078 .086
P.E.r
-.094 (-.246) -.139 -.136
-.164 +.013 -.231 -.333 -.204
(-.203) (-.310) (-.425) (-.120) (-.466) (-.371) (-.454)
.112 .111 .111 .110 .112
(.109) (.110) (.103) (.090) (.111) .107 (.087) .100 (.098) .108 (.091)
RELATION OF INTELLIGENCE TO SUCCESS 2. Motor
Adaptability
231
and Achievement in Technical Courses
The data on the maze adaptability test (Figure 2, Table 3) reveal that the Poor group in technical achievement is, in general, below the average score for the Best and Average groups, and for the entire group.10 The largest and most consistent differences in average score appear when the Best and
pared, respectively,
Average
groups
are com-
with the Poor group.
4000
3900 3800 3700
trt/rc
("CMP
36 Sf
.
3600 3500 a;
|
m
3400 3300 3200 3100
Fig. 2.
IV
V
VI
VII
VIII
I Criterion
II
Comparison
of Average Maze Adaptability Test Score for Best, AverGroups of Achievement in Dental Technical Courses
age, and Poor
III
In Table 4 the per cent values show that in the Poor group approximately two out of three cases tend to fail in one or more adaptability problems; while in the Best and Average groups a failure occurs in about one out of three cases. A further analysis of these results reveals a low consistent tendency favoring a higher average and median rank order rating and grade in technical for the successful group both in maze adaptability and learning when compared with the failure group.11 courses
i?
in one
Since 38 per cent of the 89 or
more
subjects (one adaptability problems, it seemed
withdrew from
school)
maze
failed
advisable to treat the results
scoring method which would include the failures. A total score was first computed so that all five adaptability problems would have a relatively equal weight. (This total weighted score was used in the correlations.) The total weighted score was then subtracted from 4500 (maximum time in seconds for all five problems). Group comparisons are based on these scores. They are to be interpreted as higher score equals better score. ii An adaptability problem not solved in 900 seconds was recorded as a failure. In learning a failure was defined as inability to trace the maze pattern for two successive trials without any errors. Most subjects completed the maze tests in about 1 hour; the time varied from 40 minutes to 3 hours.
in a
232 COMPARISON
OF
MAZE ADAPTABILITY TEST SCORES FOR
BEST, AVERAGE,
AND
POOR GROUPS OF ACHIEVEMENT IN DENTAL
Technical Courses
Best
Poor
Average
Criterion
I. II. III.. IV.. V. VI.. VII. VIII. .
.
.
..
,
.
No.
Av,
Median
Range
No.
Av.
Median
Range
No.
Av.
Median
13 13
3579 3642 3847
4218 4239 4239 4215
770-4347 770-4313 2532-4347 2162-4347 2162-4378 2532-4347 2162-4398 2162-4398
58
3763 3773 3676 3818 3768 3774 3685 3642
4103
1625-4375 875-4375 770-4375 770-4375 770-4375 770-4375 770-4375 770-4375
14 13
3460 3313 3632 3187 3237 3267 3566 3732
3952
803-4359
3452
803-4359 1440-4334 803-4295 803-4359 803-4378 803-4286 1440-4295
15 16
15 15 19 15
3860
3872 3825 3931 3895
4239
4116 4239 4239
59 59 56 58
57 50
57
4111
4097 4156 4111
4132 4083 4074
15 16 15 16 20 15
4134
3370 3452 3370 4116 4191
Range
CLINIC PSYCHOLOGICAL THE
Table 3
RELATION OF INTELLIGENCE TO SUCCESS
233
Table 4 Comparison op Per Cent Failures in One or More Maze Adaptability Problems for
Best, Average,
Criterion
Best.
.
.
and
Poor Groups of Achievement
Dental Technical Courses
in
38 38 50
.
Average. Poor...
II
III
IV
31 37
40 37 40
38 32 62
62
33 36 53
VI
VII
VIII
40
32 40
27
40
35
32 62
42
The coefficients of correlation, between maze adaptability scores 12 and measures of technical achievement (Table 2) are higher, thus showing better agreement than those obtained with the intelligence These correlations indicate a tendency for a lower (better) in maze adaptability to be associated with higher achievement in technical courses and vice versa. The most statistically reliable coefficients occur with average technical grade second year
test.
time
score
and
prosthetic grade
achievement
are
first year.
most
clearly
These two
measures
of technical
differentiated in the above group
comparisons. 3. Motor
Learning
and Achievement in Technical Courses
No
significant relationship appears between ability to learn a and achievement in technical courses.13 However, when two cases which fell beyond the extreme upper range of scores are eliminated, there is a marked increase in the magnitude of the coefficients of correlation, as shown by the figures in parenthesis in Table 2. The largest and most reliable coefficients are then found with average technical grade second year, prosthetic grade first and maze
second years, and operative grade first year. General Conclusions The tests in this in
differentiating
technical as most
courses.
have shown, in general, most value degrees of low and high ability in dental In this respect, the findings are to be regarded
investigation
extreme
positive. intelligence
General
appears to have less
significance
in achieve-
The correlations are based on cases successful in all five problems. Thirty-seven cases, successful in both adaptability (all five problems) and learning, were especially isolated in order to obtain a group for which the conditions of relative and complete maze performance are comparatively uni12 13
form.
THE PSYCHOLOGICAL CLINIC
234
maze adaptability. The readaptability reveal that there is a low significant relationship between ability in a task involving quick and effective adjustment to a relatively novel motor situation and achievement in dental technical courses. Maze learning ability appears to be significantly associated with achievement in dental technical courses,
ment in dental technical courses than
sults
on
maze
when two extreme cases are eliminated. The results of this investigation and related observations suggest that additional experimentation with the Miles two-story duplicate maze test may further reveal its specific value in a battery of
special aptitude
tests for
dentistry.
Psychological Corporation, Introduction
New YorTc
City
*
Dentistry involves a marked degree of "motor" or "mechanical" skill1 as well as a broad knowledge of the Medical Sciences. In actual practice, the dentist spends the greater part of his time '' working with his hands.'' An analysis of the dental curriculum reveals that 57.4 per cent of the student's
training
involves
manipu-
lative performances.2 A statement and definition of the abilities and qualifications which are most important, and the extent to which they contribute to success in dental
training and in actual practice are the subject earlier paper by the author, published in the Psychological Clinic.3- 4 The purpose of the present paper is to present data on the relation of general intelligence, ability to solve a motor problem and to learn a motor problem, respectively, to success in Dental Techof
an
nical Courses. Subjects The investigation included 90 men, the entire second year class, in the School of Dentistry, University of Pennsylvania. The class *
The writer wishes to
acknowledge his indebtedness to Dr. Charles R. School; and to Professors Edwin B. Twitmyer, Samuel W. Fernberger, and Morris S. Viteles, Department of Psychology, of the University of Pennsylvania. 1 Paterson, D. G., Elliott, R. M., et al., Minnesota mechanical ability tests, 1930, 5-11, 136 ff. "A scale was developed and used for grading occupations according to the judged amount of mechanical ability involved." Dentistry received a rating of 4.55 S.D., and is, therefore, considered as an occupation involving a high degree of mechanical ability. 2 The Carnegie Foundation for the Advancement of Teaching, Dental Education in the U. S. and Canada, Bulletin 19, 1926. 3 This study is part of a comprehensive program of research which has been outlined by the writer. 4 Schultz, R. S., A Review on the Measurement and Description of Qualifications for Dentistry and Dental Training, Psychol. Clin., 1932, 21, 172-182. Turner,
Dean of the Dental
226
RELATION OF INTELLIGENCE TO SUCCESS
227
selected because it represented a relatively homogeneous group. These students have received intensive technical training, preparatory to undertaking practical clinical work with patients. They averaged about 22% years of age, with a range from 20 to 28 years. was
Procedure 5
Two-Story Duplicate Maze was selected as a device for obtaining a measure of the ability to solve a motor problem as well as of the ability to learn a motor problem. This apparatus has the advantage of presenting a task involving the coordination of two "hands" combined with the use of the visual, tactile, and The Miles
kinaesthetic
It consists of two identical maze patterns, senses. mounted directly above the other, on a wooden box with two The task requires the movement of a stylus through open sides. one
a
stationary visible top pattern by one hand, while at the same a pencil is moved through a screened bottom pattern by the
time
other hand.6'7 First an attempt was made to obtain a measure of the various abilities and traits that may be evoked in adaptation to a relatively novel motor situation. Problems of varying difficulty in motor
adaptation
were arranged by rotating the bottom maze, with refthe top maze, to five successive positions (0?, 180?, 90?, 180? reverse, 90? reverse). Each position was to be traced as
erence to
quickly
as
possible.
After this
adaptability task, one of the above problems (180? position) was given as a learning task. The general instructions were to learn to trace through the maze pattern as quickly as possible without error. The Psychological Examination, American Council on Educareverse
5 Miles, 10, 365-377.
W.
R.,
The
Two-story Duplicate Maze,
6 Tlie formation of habits from a visual plan is aspects of the dental student's practical learning.
J.
Exper. Psychol., 1927, of the most
important learns, in laboratory demonstrations, lectures, personal instruction in practical work, etc., must be reproduced some time later. There is only a limited opportunity to perform actual movements or operations while receiving instruction. He must, therefore, depend on memory, models, and possibly imagery. In the course in Operative Dentistry the student is trained to explore and to make minutely controlled movements in unseen or limited visual fields, with the dental mirror 7
as an
For detailed
one
Much of what he
accessory.
description of procedure and method of scoring see Schultz, E. S., The Relation of Maze Adaptability, Maze Learning, and General Intelligence, Amer. J. Psychol., 1932, 44, 249-262.
THE PSYCHOLOGICAL CLINIC
228
tion,8 was used to obtain a measure of general intelligence. administered, before any maze tests were given, as a group
It
was
exami-
nation. Results The maze
significance
of the
tests is evaluated
scores on
the
intelligence
test and the
by comparisons with rank order ratings and
in dental technical courses, on the basis of which the studivided into Best, Average, and Poor groups.9 Test scores are distributed according to this classification. The measures of success include eight technical criteria. Three
grades dents
are
were
based
order
on
rating
structors; (2)
second year technical courses: (1) a General rank ability, the average of the ratings by three inan Average Operative rank order rating, the average
of
of the ratings by two instructors in operative technics; (3) a Prosthetic Technic rank order rating, estimate of one instructor. The final per cent marks in the technical courses for the first and second years yield five additional criteria. The criteria are numbered in the tables and I. General average rank order II. Average operative rank order III.
Prosthetic rank order
IV. V.
Average technical grade second Operative grade second year
VI. VII.
figures
as
follows:
year
Prosthetic grade second year Prosthetic grade first year
VIII. Operative grade first year These data are analyzed by a
study of how well the tests discriminate the Best, Average, and Poor groups of technical ability. Coefficients of correlation are also computed to obtain an index of the degree of correspondence between test in technical courses. 1. General
Intelligence
scores
and achievement
and Achievement in Technical Courses
In Fig. 1 and Table 1 the average score on the intelligence test for the Poor group is below the average for the Best and Average 8 Thurstone, L. L., and Thurstone, T. 6., The 1929 Psychological Examination, Educ. Record, 1930, 11, 101 ff. ? Approximately 68 per cent of the cases are included in the average group, and the remaining cases are divided equally between the two other groups. This division is based on the assumption that the abilities under consideration are distributed to follow the general trend of the normal probability curve.
of
Intelligence Test Scores
fob
Best, Average,
and
Poor Groups of Achievement in Dental Technical
Courses Best
Poor
Average
Criterion
I II II I IV V VI VI I VII I
No.
Av.
Median
Range
No.
Av.
Median
Range
No.
Av.
Median
Range
13 13
197 210
189 188 185
189
57-299 57-299 57-299 57-299 57-299 57-299 57-299 57-299
14 13
183 175
168 168
195
73-271 135-271 73-271 73-271 127-271 73-273 73-271 126-260
58
15 16 15 15 19 15
200 219 196 198
15 16 15 16 20
190
191
164 174
166 166
88-298 109-242 75-299 96-234 109-243
160 181
161
96-209
17
181
168 184
88-299 88-263
196 199 184 197 190
199
172 209 199
59
59 56 58 57 51 58
192
188 196 185 188
189
188 193 192 203 186 186
SUCCESS TO INTELLIGENCE OF RELATION
Comparison
229
Table 1
THE PSYCHOLOGICAL CLINIC
230
The differences are groups, and for tlie entire group of 90 cases. most pronounced when the Poor group is compared with the Best Coefficients of correlation (Table 2) between intelligence group. test scores and achievement in technical courses are low and sta-
tistically
unreliable. ?
?
*?
?
?
?
? ~
'er+7e
I Criterion Fig. 1.
II
III
IV
Best
Atera^e P??r
~_mj_
V
VI
VII
VIII
Comparison of Average Intelligence Test Score for Best, Average, and Poor Groups of Achievement in Dental Technical Courses
intelligence test appears to have most value in differentiating general ability in technical courses, as signified by the criThe
terion?average technical grade second
year.
Table 2 Correlation of Scores in Tests with Measures of Achievement
(Criteria)
in
General Intelligence No.
85-90
.
.
II. III. IV.. V. VI.. VII. VIII. .
.
.
.
Maze
Adaptability
+.104 + .208 -.031 + .227
+.161 +.189 +.130 +.063
Maze
52-55
P.E.r
Criterion I.
Dental Technical Courses
.073 .070 .071 .068
.070 .070 .070 .071
Learning
35-37
P.E.r
.297 .289 .294 .318 .279 .279 .372 .247
.086
.086 .083 .083 .085
.084 .078 .086
P.E.r
-.094 (-.246) -.139 -.136
-.164 +.013 -.231 -.333 -.204
(-.203) (-.310) (-.425) (-.120) (-.466) (-.371) (-.454)
.112 .111 .111 .110 .112
(.109) (.110) (.103) (.090) (.111) .107 (.087) .100 (.098) .108 (.091)
RELATION OF INTELLIGENCE TO SUCCESS 2. Motor
Adaptability
231
and Achievement in Technical Courses
The data on the maze adaptability test (Figure 2, Table 3) reveal that the Poor group in technical achievement is, in general, below the average score for the Best and Average groups, and for the entire group.10 The largest and most consistent differences in average score appear when the Best and
pared, respectively,
Average
groups
are com-
with the Poor group.
4000
3900 3800 3700
trt/rc
("CMP
36 Sf
.
3600 3500 a;
|
m
3400 3300 3200 3100
Fig. 2.
IV
V
VI
VII
VIII
I Criterion
II
Comparison
of Average Maze Adaptability Test Score for Best, AverGroups of Achievement in Dental Technical Courses
age, and Poor
III
In Table 4 the per cent values show that in the Poor group approximately two out of three cases tend to fail in one or more adaptability problems; while in the Best and Average groups a failure occurs in about one out of three cases. A further analysis of these results reveals a low consistent tendency favoring a higher average and median rank order rating and grade in technical for the successful group both in maze adaptability and learning when compared with the failure group.11 courses
i?
in one
Since 38 per cent of the 89 or
more
subjects (one adaptability problems, it seemed
withdrew from
school)
maze
failed
advisable to treat the results
scoring method which would include the failures. A total score was first computed so that all five adaptability problems would have a relatively equal weight. (This total weighted score was used in the correlations.) The total weighted score was then subtracted from 4500 (maximum time in seconds for all five problems). Group comparisons are based on these scores. They are to be interpreted as higher score equals better score. ii An adaptability problem not solved in 900 seconds was recorded as a failure. In learning a failure was defined as inability to trace the maze pattern for two successive trials without any errors. Most subjects completed the maze tests in about 1 hour; the time varied from 40 minutes to 3 hours.
in a
232 COMPARISON
OF
MAZE ADAPTABILITY TEST SCORES FOR
BEST, AVERAGE,
AND
POOR GROUPS OF ACHIEVEMENT IN DENTAL
Technical Courses
Best
Poor
Average
Criterion
I. II. III.. IV.. V. VI.. VII. VIII. .
.
.
..
,
.
No.
Av,
Median
Range
No.
Av.
Median
Range
No.
Av.
Median
13 13
3579 3642 3847
4218 4239 4239 4215
770-4347 770-4313 2532-4347 2162-4347 2162-4378 2532-4347 2162-4398 2162-4398
58
3763 3773 3676 3818 3768 3774 3685 3642
4103
1625-4375 875-4375 770-4375 770-4375 770-4375 770-4375 770-4375 770-4375
14 13
3460 3313 3632 3187 3237 3267 3566 3732
3952
803-4359
3452
803-4359 1440-4334 803-4295 803-4359 803-4378 803-4286 1440-4295
15 16
15 15 19 15
3860
3872 3825 3931 3895
4239
4116 4239 4239
59 59 56 58
57 50
57
4111
4097 4156 4111
4132 4083 4074
15 16 15 16 20 15
4134
3370 3452 3370 4116 4191
Range
CLINIC PSYCHOLOGICAL THE
Table 3
RELATION OF INTELLIGENCE TO SUCCESS
233
Table 4 Comparison op Per Cent Failures in One or More Maze Adaptability Problems for
Best, Average,
Criterion
Best.
.
.
and
Poor Groups of Achievement
Dental Technical Courses
in
38 38 50
.
Average. Poor...
II
III
IV
31 37
40 37 40
38 32 62
62
33 36 53
VI
VII
VIII
40
32 40
27
40
35
32 62
42
The coefficients of correlation, between maze adaptability scores 12 and measures of technical achievement (Table 2) are higher, thus showing better agreement than those obtained with the intelligence These correlations indicate a tendency for a lower (better) in maze adaptability to be associated with higher achievement in technical courses and vice versa. The most statistically reliable coefficients occur with average technical grade second year
test.
time
score
and
prosthetic grade
achievement
are
first year.
most
clearly
These two
measures
of technical
differentiated in the above group
comparisons. 3. Motor
Learning
and Achievement in Technical Courses
No
significant relationship appears between ability to learn a and achievement in technical courses.13 However, when two cases which fell beyond the extreme upper range of scores are eliminated, there is a marked increase in the magnitude of the coefficients of correlation, as shown by the figures in parenthesis in Table 2. The largest and most reliable coefficients are then found with average technical grade second year, prosthetic grade first and maze
second years, and operative grade first year. General Conclusions The tests in this in
differentiating
technical as most
courses.
have shown, in general, most value degrees of low and high ability in dental In this respect, the findings are to be regarded
investigation
extreme
positive. intelligence
General
appears to have less
significance
in achieve-
The correlations are based on cases successful in all five problems. Thirty-seven cases, successful in both adaptability (all five problems) and learning, were especially isolated in order to obtain a group for which the conditions of relative and complete maze performance are comparatively uni12 13
form.
THE PSYCHOLOGICAL CLINIC
234
maze adaptability. The readaptability reveal that there is a low significant relationship between ability in a task involving quick and effective adjustment to a relatively novel motor situation and achievement in dental technical courses. Maze learning ability appears to be significantly associated with achievement in dental technical courses,
ment in dental technical courses than
sults
on
maze
when two extreme cases are eliminated. The results of this investigation and related observations suggest that additional experimentation with the Miles two-story duplicate maze test may further reveal its specific value in a battery of
special aptitude
tests for
dentistry.
