The Wechsler Intelligence Test-A Brief Guide

The Wechsler Intelligence Tests are the most commonly used instruments to assess intelligence of children, adolescents and adults. The tests are used world-wide and generate valid and reliable reports of an individuals intellectual functioning. They are used in a variety of settings from school to clinics and in organisational and career guidance settings. It is not uncommon for people to be confused about what the tests measure and how they measure it. This is a brief guide to the Wechsler Intelligence Tests.

The test is divided into two broad categories, each containing a number of sub-tests which are administered to calculate person’s results. The two categories are Verbal scale and a performance scale.

The Verbal Scale

The verbal scale measures verbal abilities such as comprehension of social situations, recall of digits forward and in reverse, long term memory of facts, and verbal ability to think abstractly and make connections of things into categories. These skills are important for school success and in negotiating the social world and understand it. The skills measured are influenced to a high degree by level of education and the efficiency of teaching across the life span. The verbal scale is also useful for assessing attention and concentration skills.

The Performance Scale

The Performance scale of the Wechsler tests is meant to assess intellectual skills without requiring a verbal response. It is therefore a useful way to assess people who cannot speak or who have expressive language difficulties. The scale consists of a number of items such as putting puzzles together, copying visual codes rapidly under the pressure of time, analysing and putting abstract patterns of blocks together and spotting what’s missing in pictures. Although it is thought of as a non-verbal test it is obvious that when looking at visual objects a certain amount of self-talk is going on in a person’s head. However, it’s reliance on non-verbal responses makes is a good companion to the verbal tests on the Wechsler.

The Full Scale Score

The results of both Verbal and Performance scales are combined in a series of statistical computations by the examiner and totalled into a Full Scale score which is the equivalent of an IQ score. The value of the Full Scale score is it indicates, in a general sense, what the person’s overall level of intellectual functioning is but it is influenced at times by wide discrepancies between the Verbal and Performance scales. Therefore it can be either an accurate, overestimate or underestimate of a person’s general level of intelligence.

This brief overview does not do justice to the intricacies of the Wechsler scales but it will, I hope, assist people in coming to a more complete understand of intelligence test results.