Wechsler Adult Intelligence Scale (WAIS): The definitive adult IQ test

About the Wechsler Adult Intelligence Scale (WAIS)

In 1955 David Wechsler published the Wechsler Adult Intelligence Scale, a major revision of his 1939 Wechsler-Bellevue. The WAIS was renormed on a representative US sample (1,700 adults aged 16-64) and introduced the deviation-IQ scoring system: rather than the mental-age-divided-by-chronological-age IQ that Terman had used since 1916, Wechsler scaled raw scores so the population mean was 100 and the standard deviation was 15. This was a fundamental improvement and has been used by every IQ test since.

The WAIS had 11 subtests: 6 Verbal (Information, Comprehension, Arithmetic, Similarities, Digit Span, Vocabulary) and 5 Performance (Digit Symbol, Picture Completion, Block Design, Picture Arrangement, Object Assembly). Each subtest yielded a scaled score; the sum produced Verbal IQ, Performance IQ, and Full Scale IQ.

The WAIS dominated adult intelligence assessment for 25 years until the WAIS-R (1981), then WAIS-III (1997), WAIS-IV (2008), and now WAIS-5 (2024). The basic 11-subtest structure has been refined but not abandoned. WAIS-IV is the world's most-administered adult IQ test, with millions of administrations per year. Pearson holds active copyright; the original 1955 manual is widely cited but the items themselves are commercially protected.

The 11 subtests

Sample Items (Illustrative)

Items are presented orally or visually, and responses are scored based on accuracy, completeness, and sometimes speed, depending on the subtest. Each subtest focuses on a specific cognitive ability and requires different types of responses, from verbal answers to physical manipulation of objects.

These are illustrative samples, not actual items from the protected test.

Source

All test materials and historical content on this page are transcribed from:

Wechsler, D. (1955). Manual for the Wechsler Adult Intelligence Scale. New York: Psychological Corporation.

WAIS items are copyrighted (Pearson/NCS Pearson, successor to The Psychological Corporation). We document the test's history and significance with illustrative sample items, not actual WAIS items.