EDS 711
Spring 2015
http://www.thinktonight.com/WISC_IV_subtests_s/331.htm
Behavior Sampled by Intelligence Tests.
WISC IV
The WISC IV has been normed on normal peers and for special education populations:
Mental Retardation (MR), Attention-Deficit / Hyperactivity Disorder (AD/HD), Learning Disabilities
(LD), both AD/HD and LD, Traumatic Brain Injury (TBI), etc.
WISC-IV (which is an update of the WISC-III) indicates significant advances in the understanding of
cognitive abilities.
Time Required: Administered between 65 and 80 minutes, the WISC-IV contains 10 core subtests and 5
additional subtests. These are summed to four indexes :
Verbal Comprehension Index (VCI): Requires verbal conceptualization, stored knowledge access and oral
expression. Orally presented questions that assesses common-sense reasoning, reasoning out or
retrieving word associations, and the ability to describe the nature or meaning of words. Knowledge
acquired from one's environment. Verbal expression required (length of response varies). One of the best
predictors of overall intelligence.
1. Similarities
2. Vocabulary
3. Comprehension
(Information)
5. L (Word Reasoning)
Perceptual Reasoning Index (PRI): Requires visual perception, organization and reasoning with visually
presented, nonverbal material to solve the kinds of problems that are NOT school taught.
The Block design also requires spatial processing, visual-motor coordination and the ability to apply all
skills in a quick, efficient manner. The highest scores reflect both accurate and very quick responses.
Picture Concepts score may differ from these other subtest because of the effect of language on the
performance.
1. Block Design
2. Picture Concepts
3. Matrix Reasoning
4. L (Picture Completion)
1. Digit Span
2. Letter-Number Sequencing
3. L (Arithmetic)
Processing Speed Index (PSI): Requires visual perception and organization, visual scanning, and the
efficient production of multiple motor responses. These tasks require executive control of attention and
sustained effort for a 2-minute period of time while working with simple visual material as quickly as
possible. Performance on Coding is also dependent on paired-associative learning.
1. Coding
2. Symbol Search
3. L (Cancellation)
The WISC-IV has a total of 15 subtests, 10 are retained from the WISC-III
These are the five new subtests:
1. Word Reasoning
2. Matrix Reasoning
3. Letter-Name Sequencing
4. Symbol Search
5. Cancellation
WISC IV
Dr. Sanford
1
EDS 711
Spring 2015
One Full Scale IQ (FSIQ), which range from lowest 40 to highest 160 points. Subtests are given for
additional examination of processing abilities. The age range for this test is between 6 years and 16 years
11 months. In terms of difference in scores, an individual who has taken the WISC-III, then retested with
the WISC-IV may show a 5-point drop in FSIQ. This is due to new aspects of the test, and the novelty of
some of the new items and subtests.
Object Assembly subtest from the WISC III is gone.
On the WISC III there was Picture Arrangement, now on the WISC IV there is Picture Concepts, under
Perceptual Reasoning Index.
Parents of child with NVLD were concerned about the loosing these two subtests:
Object Assembly and the Picture arrangement.
Scoring:
Current reports show that most students re-tested with the WISC-IV will have approximately a 5 point
discrepancy, lower (to the negative) because of this newer version of WISC, its novelty and its increased
difficulty.
With 4 composite scores (vs. 2 as is the case with the WISC III), there is no standard discrepancy
formula, it now all has to be evaluated in terms of the child's ability, test results, current educational
functioning, achievement test expectations based on ability, evaluation of the subtests as well as
evaluation of the composite sets.
Some evaluators have suggested that a 19-point discrepancy in the VCI/PRI composites may warrant
further investigation.
Standard deviation is 15 points, it is not clear that these score will tell enough about the child's areas of
weakness.
The Verbal Scale
Measures how well children are able to express themselves verbally and how well they are able to
understand what is being said to them.
Performance Scale measures the nonverbal areas of being able to perceive
spatial relationships; such as in putting puzzles together, and being able
to transfer visual information rapidly.
Another way to organize these subtests:
Verbal Comprehension:
Vocabulary, similarities, information
Perceptual Organization:
Picture completion, block design, matrix reasoning
Working memory:
Arithmetic, digit span, letter-number sequencing
Processing speed:
Digit-symbol coding, symbol search
WISC IV
Dr. Sanford
2