Gifted and Talented - Learning Disabled Test

WISC = Wechsler Intelligence Scale for Children

Many psychologists use the Wechsler Intelligence Scale for Children (WISC), third edition, to identify learning disabilities. The WISC is an intelligence test that can be administered only by a licensed psychologist or tester. The scores may be interpreted in several different ways by specialists and nonspecialists alike who understand the significance of the numbers. A WISC score is derived from the scaled combination of two sets of subtests, Verbal and Performance. Each of these two categories has its own total, which is derived from the scaled combination of 6 subtest scores. The Wechsler Intelligence Scale for Children(r)-Fourth Edition, which added several new subtests and eliminated others, has recently become available. The WISC-IV comprises 10 core and five supplemental subtests, which are grouped into four indices-verbal comprehension, perceptual reasoning, working memory and processing speed. Scores from each index, based on the core subtests only, are combined to create a child's total score, or Full Scale IQ (FSIQ).

The following information relates to the The Wechsler Intelligence Scale for Children (WISC) Third Edition.

Verbal

Information - fund of general knowledge
Similarities - verbal abstract reasoning
Arithmetic - numerical reasoning, attention and short-term memory for meaningful information
Vocabulary - knowledge of word meanings
Comprehension - social comprehension and judgment
Digit Span - short-term auditory memory for non-meaningful information

Performance

Picture Completion - attention to visual detail
Coding - visual-motor skills, processing speed
Picture Arrangement - attention to visual detail, sequential reasoning
Block Design - visual abstract ability
Object Assembly - part-whole reasoning
Mazes - graphomotor planning, visual-motor coordination and speed

Each subtest delivers a scaled score, which may range from 1 (lowest) to 19 (highest).

Gifted students typically have very high scores in the abstract subtests and somewhat lower scores in the concrete subtests. Gifted students with disabilities typically have a wide "scatter" or discrepancy within either or both the verbal and performance sections. They might demonstrate much lower scores in digit span, which tests a student's ability to hear and repeat-forward and backward-a meaningless string of numbers, or coding, which tests visual-motor integration. Students with weak visual memory, anxiety, and difficulty with concentration or pencil manipulation may score lower than typically expected. School districts typically use a discrepancy between the verbal and performance sections as an indicator of a learning disability, although they might not provide special services unless there are additional indicators. Yet, gifted students with learning disabilities might not demonstrate the typical discrepancy between the verbal and performance sections.

Although the WISC places some ethnic groups at a disadvantage, it is an excellent way to discern a student's strengths and limitations.

IQ Scores

The following table is an example of how WISC scores might be categorized by some researchers. The standard deviation (SD=15 or SD=16 depending on the test instrument) was used to determine the breakpoints between categories.
85-99 Lower normal 1 SD below the mean
100-114 Upper normal
115-129 Bright 1 SD above the mean
130-144 Gifted 2 SD above the mean
145-159 Highly gifted 3 SD above the mean
160-??? Profoundly gifted 4 or more SD above the mean

The standard deviation (SD) of the most commonly used IQ tests is 15 or 16. Tables such as the one above commonly use 15-point spreads. At IQ=130, the "gifted" child is as "different," in intellectual abilities, from the "average child" (IQ 85-115), as a child whose IQ is 70. IQ scores do not tell the whole story; however, they are a useful indicator of individual differences, especially when used to inform instruction.

*Wechsler Intelligence Scale for Children (WISC) Fourth Edition

The WISC-IV comprises 10 core and five supplemental subtests, which are grouped into four indices-verbal comprehension, perceptual reasoning, working memory and processing speed. Scores from each index, based on the core subtests only, are combined to create a child's total score, or Full Scale IQ (FSIQ).

Three subtests from previous editions-mazes, object assembly and picture arrangement-were dropped from the fourth edition in favor of newer working memory and processing speed subtests that researchers discovered are more accurate and better measures of intelligence.

The WISC-IV includes several new subtests. In the new word reasoning subtest, a child receives multiple verbal clues then must determine what those clues mean. For example, the child might identify a mop based on verbal clues that describe its form and function.

The new matrix reasoning subtest measures a child's non-verbal reasoning ability. In this exercise, a child sees a partially filled grid and then selects the item that completes the grid. For example, the child might see two sets of shapes, such as stars and pentagons, with one set arranged in a certain color sequence. The child then must determine the correct color sequence of the second set of shapes to complete the grid.

In the new picture concepts subtest, which measures a child's ability to categorize, the child sees multiple rows of objects and selects those objects that are similar based on an underlying concept. For example, the similar items might be trees or animals.

The new letter-numbering sequence subtest measures working memory. In this exercise, a child hears a mixed combination of letters and numbers. The child first repeats the numbers in numerical order and then the letters in alphabetical order.

A new timed subtest called "cancellation" tests a child's processing speed. In this exercise, a page is covered with pictures of animals and other common objects, either randomly scattered on the page or arranged in rows and columns. The child then marks through-or cancels-the animals as quickly as possibly.

*From The Psychological Corporation, http://marketplace.psychcorp.com/