Wechsler Adult Intelligence Scale

The Wechsler Adult Intelligence Scale (WAIS) is an adult intelligence test developed by David Wechsler. The WAIS is one of many available tests to measure intellectual or cognitive abilities. An intelligence test is designed to measure intelligence according to the theoretical model underlying the test’s characterization of intellectual ability. This entry describes the theoretical basis as well as the history and development of the WAIS as a measure of intellectual ability.

Wechsler defined intelligence as “the aggregate or global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment” (Wechsler, 1958, p. 7). Thus, the score obtained on the scale designed by Wechsler was thought to represent general mental ability composed of qualitatively distinct abilities. Wechsler thought it was ...