By David Wechsler


It is an individually administered clinical instrument for measuring an adult's intellectual ability
aged 16 years through 89 years.

WAIS III (3rd Edition) has three composite scores, that should be provided to you:
  1. Verbal IQ (VIQ)
  2. Performance IQ (PIQ)
  3. Full Scale IQ (FSIQ)

14 subtests of the WAIS-III

(The preious verison was the WAIS-R, consists of 11 subtests divided into two parts, verbal and performance.)

The subtest are divided into two parts, verbal 7 and performance 7.
Verbal IQ (VIQ):

Degree of general information acquired from culture
(e.g. Who is the premier of Victoria?)

Ability to deal with abstract social conventions, rules and expressions
(e.g. What does - kill 2 birds with 1 stone metaphorically mean?)

Concentration while manipulating mental mathematical problems
(e.g. How many 45c. stamps can you buy for a dollar?)

Abstract verbal reasoning
(e.g. In what way are an apple and a pear alike and/or unalike?)

The degree to which one has learned, been able to comprehend and verbally express vocabulary
(e.g. What is a guitar?)

Digit span
(e.g. Digits forward: 123, Digits backward 321.)

Letter-Number Sequencing
attention and working memory

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Performance IQ (PIQ):

Picture Completion
Ability to quickly perceive visual details

Digit Symbol - Coding
Visual-motor coordination, motor and mental speed

Block Design
Spatial perception, visual abstract processing & problem solving

Matrix Reasoning
Nonverbal abstract problem solving, inductive reasoning, spatial reasoning

Picture Arrangement
Logical/sequential reasoning, social insight

Symbol Search
Visual perception, speed

Object Assembly
Visual analysis, synthesis, and construction

Optional post-tests include Digit Symbol - Incidental Learning and Digit Symbol - Free Recall.

WAIS-III Subtests Grouped According to Indices
In addition to the Verbal and Performance IQ scores, the following four composite scores.

Full Scale IQ (FSIQ) is comprises of the four composite scores.

Verbal Comprehension Index (VCI): Requires verbal conceptualization, stored knowledge access and oral expression.  Orally presented questions that assess 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 overal intelligence.

Perceptual Organization Index (POI): 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 preformance.

Working Memory Index (WMI): Requires working memory processes applied to the manipulation of orally presented verbal sequences.  The ability to temporarily retain information in memory, by performing some operation or manipulation with it, and produce a result.  Involves attention, concentration, mental control, reasoning.  Essential component of other cognitive higher order progresses.   Closely related to achievement  and  learning (People with Learning Disability frequently affected).

Processing Speed (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.

WAIS-III by Wechsler, D. (1997),
For more information  please visit these other websites:

Harcourt Assessment, Inc, WAIS-III

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Last updated September 27, 2006
By Melody Orfei