Intelligence
Tests
There are several different tests which are used to assess mental
abilities. The two most commonly used with gifted children are
the Wechsler Intelligence Scale for Children® (WISC) and the
Stanford-Binet. The Stanford-Binet has a higher range and is the
test of choice for highly gifted children.
Apparently,
neither of the current tests adequately measure abilities of children
whose true IQ is above 130. A child from a background offering
limited exposure to situations examined in these tests may not
do as well. Results of intelligence tests are usually reported
in a single standard score, an Intelligence Quotient or IQ.
The
schools may choose to use other kinds of tests in their screening
processes for admission to Talented and Gifted (TAG) programs.
Schools most likely will choose tests that will identify students
that meet their specific program goals and budgets. .
The WISC and Stanford-Binet are tests that must be administered
by a psychologists. When choosing a psychologist or other professional
to administer an IQ test, you should insure that the tester is
familiar with the characteristic behaviors of gifted children.
Otherwise, the test results may reflect the test administrators'
expectations, like looking for a learning disability, rather than
seeking the child's abilities. Experience has taught me that if
you see an extreme discrepancy in one or more of the subtests,
you may actually be looking at some sort of disability.
One of the best resources I have encountered that describes this
phenomenon is in the book "Upside-down Brilliance: The Visual
Spatial Learner" by Linda Kreger Silverman. In this book
Dr. Silverman describes how to assess if the test charts you are
looking at indicate some sort of disability. Another book available:
Intelligent Testing with the WISC-III by Alan S. Kaufman.
Books:
"Intelligent
Testing with the WISC-III (Wiley Series on Personality Processes)"
by Alan S. Kaufman.
"Upside-Down
Brilliance: The Visual Spatial Learner" by Linda
Kreger Silverman
I.Q. SCORES
The following is one of the more commonly used categorizations
of IQ scores. Like everything else, different people have different
ideas about where the breakpoints should be for each category
and the numbers of people who fit into each category. Some of
the more recent research seems to indicate that there are more
individuals in the 160+ range than would be predicted by the Normal
Distribution upon which the numbers below are based.
85
Lower normal
100 Upper normal
115 Bright
130 Gifted
145 Highly gifted (approximately 1 in 1,000)
160 Exceptionally gifted (approximately 1 in 100,000)
180+ Profoundly gifted (approximately 1 in 1,000,000) |
Understanding the Wechsler Tests
The Wechsler Intelligence Scale for Children WISC is a battery
of tests for 6 to 17 year olds that evaluates intellectual abilities.
The WISC consists of two scales, the Verbal Scale and the Performance
Scale. Each of these scales has several subtests.These
sub-test scores are scaled from 1 - 19, with 10 being an average
score. The Verbal Scale measures language
expression, comprehension, listening, and the ability to apply
these skills to solving problems. The examiner gives the questions
orally, and the child gives a spoken response. The Performance
Scale assesses nonverbal problem solving, perceptual organization,
speed, and visual-motor proficiency. Included are tasks like puzzles,
analysis of pictures, imitating designs with blocks, and copying.
It
is important to review the sub-test scores; they can identify
strengths and weaknesses of the child. One or two unusually low
sub-test scores may indicate a potential learning disability,
which could lower a child's overall IQ score and make a gifted
child look "average". Relatively low scores mixed with
higher scores could make a gifted child look 'non-gifted' when
in fact he could be "twice exceptional".
[See
our pages on "twice exceptional"]
Ceiling
effects, or high scores on sub-tests may also be particularly
misleading in cases where the child has widely varying abilities.
If the student has two or more sub-test scores in the ceiling
range (17 - 19) indicating that the child reached the ceiling
of the test, he might be re-tested using a test designed to differentiate
highly gifted children. If your student "maxes-out"
one or more subtests you can safely assume that your student is
probably "gifted" if not highly gifted in that area.
Having the Stanford Binet administered at that point is probably
a good idea if you really want to know if your student is highly
gifted. Recognizing that your student is gifted in one of the
subtests may also help you determine a dominant learning style.
[See
our pages on "learning styles"]
Intelligence
tests are samples of problem solving abilities and learned facts,
and are good predictors of future learning and academic success.
However, there are several factors that the tests do not measure.
For instance, they cannot determine motivation, curiosity, creative
talent, work habits, study skills, or achievement in academic
subjects. These should also be considered when interpreting the
scores in this report.
Several
scores are obtained from the WISC. Scale scores (Verbal and Performance
IQ scores) are the summary measures of verbal and performance
skills, and the Full Scale IQ is an index of general intellectual
functioning.
Scores
on the WISC of 135 or above may be artificially low since the
test itself has a maximum of 150.
A typical report summary may look like:
IQ
Scale / Index |
IQ Scale Score |
Percentile |
Confidence Interval |
Range |
Verbal
IQ |
|
|
|
|
Performance
IQ |
|
|
|
|
Full
Scale IQ |
|
|
|
|
Verbal
Comprehension Index |
|
|
|
|
Perceptual
Organization Index |
|
|
|
|
Freedom
From Distractibility Index |
|
|
|
|
Processing
Speed Index |
|
|
|
|
A
Percentile rank expresses the relative position of a score. For
example, a percentile rank of 98 means that a child has scored
as well as or better than 98% of students of the same age on that
subtest. The confidence interval indicates the probable range
of scores which can be expected when this individual is retested.
Subtest scaled scores (listed below) range from 1 to 19.
|
Scaled Score |
%ile Rank |
Description |
Verbal
Subtests |
|
|
|
Information |
|
|
General
factual knowledge, long term memory |
Similarities |
|
|
Abstract
reasoning, categories, relationships |
Arithmetic |
|
|
Attention,
concentration, numerical reasoning |
Vocabulary |
|
|
Word
knowledge, verbal fluency |
Comprehension |
|
|
Social
judgment, common sense reasoning |
Digit
Span |
|
|
Short
term auditory memory, concentration |
Performance
Subtests |
|
|
|
Picture
Completion |
|
|
Alertness
to essential detail |
Coding |
|
|
Visual
motor co-ordination, speed, concentration |
Picture
Arrangement |
|
|
Sequential,
logical thinking |
Block
Design |
|
|
Spatial,
abstract visual problem solving |
Object
Assembly |
|
|
Visual
analysis, construction of objects |
Symbol
Search |
|
|
Speed
of processing novel information |
Mazes |
|
|
Fine
motor co-ordination, planning, following directions |
|
|