Wechsler IQ Tests: Popular and Pervasive

Wechsler IQ tests have been used for more than 50 years. The Wechsler Adult Intelligence Scale (WAIS) is among the most widely used scale for IQ tests. The present scale is the third edition, known as the WAIS-III.

Psychologist David Wechsler (1896-1981) created what we now refer to as Wechsler IQ tests. He developed the first Wechsler Bellevue Scale in 1939 and some 15 years later revised it into the WAIS. His study of memory loss before the First World War provided a foundation for his curiosity about intelligence and how it is tested.

Wechsler became interested in children's IQ scores. He considered the effect of environment on intelligence and decided that a person's IQ is open to influences. As well, he observed that qualities such as persistence can affect general intelligence. He designed intelligence tests that could be applied to a range of ages.

If you take the Wechsler test, you can expect to receive a full-scale IQ score (which represents general intelligence), a verbal IQ score and a performance IQ score. You would be scored on intelligence in verbal and analytic reasoning. There are 11 separate subtests (the verbal scale is six subtests and the performance scale is five subtests). You would receive scaled scores on the subtests, as well.

The types of Wechsler intelligence tests include the Wechsler Pre-School and Primary Scale of Intelligence (WPPSI) for ages three to seven years; the Wechsler Intelligence Scale for Children (WISC) for ages seven to 16; and the Wechsler Adult Intelligence Scale (WAIS) for ages 16 and above.

The Verbal WAIS scales include questions about information (measuring general knowledge), digit span, vocabulary, math, comprehension and similarities. The performance WAIS scales include tests of picture completion, picture arrangement, block design, and digit symbol and object assembly.

Wechsler IQ tests and the scale have been adapted in various countries and there have been attempts to make the scale more culturally fair.