WAIS is a general test of intelligence (IQ), published in February 1955 as a revision of the Wechsler-Bellevue test (1939), standardised for use with adults over the age of 16.

Intelligence is quantified as the global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment. The full scale is broken down to verbal scale (6 subtests) and the performance scale (5 subtests).

VERBAL:

• Information. (e.g. Who is the premier of Victoria?)
• Comprehension. (e.g. What does - kill 2 birds with 1 stone metaphorically mean?)
• Arithmetic. (e.g. How many 45c. stamps can you buy for a dollar?)
• Similarities. (e.g. In what way are an apple and a pear alike?)
• Vocabulary. (e.g. What is a guitar?)
• Digit span. (e.g. Digits forward: 123, Digits backward 321.)

PERFORMANCE:

• Picture completion.
• Picture and sequence arrangement.
• Block design.
• Object assembly.
• Digit symbol.

Wechsler's tests provide three scores: 1: a verbal IQ 2: a performance IQ 3: a composite, single IQ score based on the combined scores.

WAIS-R was standardised in 1981 on a sample of 1,880 US subjects, ranging from 16 to 74 years of age, broken down into 9 different age groups 16-17, 18-19, 20-24, 25-34, ..., 70-74 yrs. It is considered to have very strong reliability. The current version is WAIS-III (1997).

WAIS test has found to be appropriate for use with those over 74. For persons under 16, Wechsler intelligence scale for children (WISC, 7-16 yrs) and Wechsler pre-school and primary scale of intelligence (WPPSI, 3-7 yrs) are used.

Notes: An IQ score can be obtained without administering the verbal section of the test since each section yields its own score. Neuropsychologists use the technique on people suffering brain damage as it leads to links with which part of the brain has been affected.