Wechsler Adult Intelligence Scale - Fourth UK edition (WAIS-IV uk)

Pearson Assessment

Summary of Test Review

General description of Test

 

Test Review Summary

Test Name:Wechsler Adult Intelligence Scale - Fourth UK edition (WAIS-IV uk)
Author of Original Test: David Wechsler
Local test distributor / publisher:Pearson Assessment
Date of Current Review:March 2010
Date of Publication of Current Review / Edition:27 Mar 2012
Type of Test:General Ability
Verbal Ability
Non-verbal Ability
Memory
Perceptual reasoning
Processing speed
Main Area of Use:Psycho-clinical
Psycho-neurological
Forensic
Educational
Constructs Measured:General Ability
Verbal Comprehension
Perceptual Reasoning
Working Memory
Processing Speed
Administration Mode:Interactive individual administration
Response Mode:Oral interview
Manual operations
Paper and pencil
General Description of Test:The Wechsler Adult Intelligence Scale – Fourth UK Edition (WAIS-IV UK) is an individually administered clinical instrument designed to assess the cognitive ability of adolescents and adults aged 16 to 90 years. The WAIS-IV is a revision of the WAIS-III. In addition to the inclusion of 3 new subtests, there are changes to the administration of several other subtests, and to the recording and scoring of most of them. The WAIS-IV provides estimates of Full-Scale IQ, an overall measure of intellectual ability, and four composite Index scores that provide measures of component abilities: Verbal Comprehension, Perceptual Reasoning, Working Memory and Processing Speed. However, the Verbal IQ and Performance IQ scores provided by earlier versions of the WAIS have been discontinued (similar to the changes in the WISC-IV). In addition to Full-Scale IQ the WAIS-IV also provides a General Ability Index, which is derived from the Verbal Comprehension and Perceptual Reasoning Indices. This provides a measure of intellectual ability that is less dependent on working memory and processing speed, which might be more appropriate for some populations (e.g. where neuropsychological problems with working memory or physical problems affecting processing speed are evident). The WAIS-IV consists of 10 core subtests and 5 supplemental subtests. The Full-Scale IQ score is calculated from the scores obtained on the 10 core subtests, and the Index scores are calculated from the scores obtained on 2-3 subtests. The Supplemental subtests are used as alternatives to core tests (a maximum of two substitutions) if needed, and to provide further information about specific abilities if required. A number of Process Scores can also be calculated, which also provide more detailed information about specific cognitive abilities. The subtest structure of the WAIS-IV is as follows: - The Verbal Comprehension index measures knowledge of verbal concepts and includes tasks in which the examinee answers factual questions, gives the meaning of words and demonstrates the ability to express concepts and ideas. The core subtests are: Similarities, Vocabulary and Information; there is one supplemental subtest, Comprehension. - The Perceptual Reasoning index measures non-verbal thinking and visuo-spatial processing. It requires integrating visual stimuli and reasoning non-verbally to solve problems. The core subtests are: Block Design, Matrix Reasoning and Visual Puzzles (new); there are two supplemental subtests, Figure Weights (new) and Picture Completion. - The Working Memory index measures number ability, sequential processing and attention span. The core subtests are: Digit Span and Arithmetic; there is one supplemental subtest, Letter-Number Sequencing (although this is only for examinees aged 16-69). - The Processing Speed index measures speed of response to non-verbal stimuli (including both thinking and motor response). The core subtests are: Symbol Search and Coding; there is one new supplemental subtest, Cancellation (again only for examinees aged 16-69). The Full-Scale and Index scores provided by the WAIS-IV are standardized to a mean of 100, and a standard deviation of 15 with percentile equivalents and confidence intervals, and there are statistical tables to facilitate an analysis of strengths and weaknesses. The IQ range measured is 40-160 (extended relative to earlier versions).

 


Full Test Review

BPS and RQTU members login now