This IQ test was designed by David Wechsler in 1955 who thought that the Stanford-Binet IQ test had limitations to measure intelligence.
According to him, the Stanford-Binet test was designed for children only and was not suitable for adults. This is why he came up with his own test.
The Binet test was more like a self test in the early days because the result was determined by dividing the mental age of the person with their chronological age. Oh the other hand, the WAIS test involved comparing the test score among people of same age. Later on, the modern Binet test also adopted this way of determining results.
Five factors that are being tested on this test: