Intelligence tests Wechsler Tests Wechsler Adult Intelligence Scale

Intelligence tests Wechsler Tests

Wechsler Adult Intelligence Scale – WAIS Original in 1939 – W-B I n WAIS-III - 1997 n Ages 16 through 89 n

Wechsler Intelligence Scale for Children WISC Original in 1949 n Ages 6 through 16 n WISC-R in 1974 n WISC-III in 1991 n WISC-IV in 2003 (CHC model) n

Cattell-Horn-Carroll (CHC) model Started with Gf-Gc theory (fluid/crystallized) n General factor of intelligence (g) n Specific abilities (number varies) n

Wechsler Preschool and Primary Scale of Intelligence WPPSI Original in 1963 n Ages 3 to 7 years n WPPSI-R in 1989 n WPPSI-III in 2002 n

Common features Full Scale IQ n Individually administered n 50 -70 minutes administration time n Normative data n 12 – 15 subtests n Comprehensive manuals n

Different features WAIS and WPPSI n Full Scale IQ n Verbal IQ n Performance IQ WISC n Full Scale IQ Verbal Comprehension index Perceptual Reasoning index Working Memory index Processing Speed index

Sub-tests n n n n Picture completion Information Coding Similarities Picture arrangement Arithmetic Block design Vocabulary Object assembly Comprehension Symbol search Digit span Mazes

Factor Analysis of WISC-III Factor I – Verbal Comprehension information similarities vocabulary comprehension

Factor II – Perceptual Organization (Reasoning) picture Completion picture arrangement block design object assembly

Factor III – Freedom from distractibility (Working Memory) arithmetic digit span

Factor IV – Processing Speed coding symbol search

Case studies n Examples of profiles