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Wide Range Intelligence Test

The Wide Range Intelligence Test is a test comparable to the Wechsler Abbreviated Scale of Intelligence, measuring general intelligence, based on four tasks assessing verbal and visual cognitive abilities. It was developed in the year 2000 in order to offer a shorter and therewith more efficient alternative to the traditionally more extensive and time-consuming intelligence tests in use.

History

To examine the validity of the Wide Range Intelligence Test (WRIT) it is helpful to take a broader look at the history of intelligence testing.

The starting point of intelligence began with Francis Galton in the late 19th century . Intelligence testing by Galton was based on the measurement of sensory and motor coordination. Alfred Binet and Theodore Simon are regarded as the fathers of modern intelligence measuring. They measured mental processes like memory, comprehension and imagination to assess intelligence. By not focusing on sensory and motor capabilities they founded the modern intelligence measurement. They examined pupils at school to find out “the gifted ones” and “ the impaired ones”. Another step forward in measuring intelligence came by Lewis Terman. Together with Binet he modified and standardized the next step of intelligence measurement. They examined soldiers in world war I. To overcome shortcomings of the Stanford Binet intelligence test Wechsler developed the Wechsler-Bellevue scale of intelligence. Verbal and Visual IQ of the WRIT – domains are based on dichotomies seen also in Wechsler’s theory of mental abilities and in the Cattell-Horn theory. The WRIT, a test developed in 2000 was mainly influenced by the Kaufmann Brief Intelligence Test (K-BIT). This test consists tasks measuring verbal facility and nonverbal reasoning and provides a composite score that can be used to estimate intellectual functioning for persons age 4 to 90. By using subtests, Kaufmann influenced other practitioners to construct new tests consisting a small number of subtests .

Test format

The "Wide Range Intelligence Test" is executed on participants between 4 to 85 years and in the time of less than 30 minutes. It is administered individually on each subject. The test is generally divided into two subcategories with each two subtests, so in total there are four subtests. The one subcategory assesses the Verbal IQ based on the Verbal Intelligence Scale. The relating subtests are called "Vocabulary Test" and "Verbal Analogies Test". The other subcategory assesses the Visual IQ based on the Visual Intelligence Scale. The relating subtests are called "Matrices Test" and "Diamonds Test". The Verbal IQ and the Visual IQ generate a combined General IQ. The test starts with the "Visual Subtest of Matrices" followed by the "Verbal Subtest of Verbal Analogies" and "Visual Subtest of Diamonds" and ends with "Verbal Subtest of Vocabulary". Thus both subcategories alternate.

Visual Subtest of Matrices

The subtest of Matrices is the first test being assessed. It is the first part to conduct the Visual IQ. Hereby the subject needs to evaluate a series of pictures by selecting the options that best show a visual-perceptual relationship. The directions are presented verbally to the subject and there´s a time limit of 30 to 45 seconds to select the pictures. This subtest requires visual-spatial reasoning, as an understanding for abstract visual-perceptual relationships. This subtest measures spatial ability, sequential reasoning, attention, impulsiveness and visual acuity.

Verbal Subtest of Verbal Analogies

The subtest of Verbal Analogies is conducted as the second test of the WRIT. It is the first part of conducting the Verbal IQ. Therefore, the subject needs to find a word which best forms an analogy in an existing sentence. The instructions are again presented verbally, without any visual stimuli or sample items being provided. To successfully perform this test, the subject is required to understand oral language and to provide a correct verbal response. This subtest measures auditory processing, verbal reasoning, receptive and expressive language ability, and long- and short-term memory.

Visual Subtest of Diamonds

The subtest of Diamonds is administered as the third subtest of the WRIT. It is a subtest belonging to the subcategory of the Visual IQ. The subjects have to reproduce two- or three-dimensional patterns using cardboard chips as single or multiple diamonds within a specific time limit (i.e. 30 to 105 seconds). This subtest measures spatial ability, visual acuity, visual-motor coordination, short-term visual memory, manipulative skills, but minimal manual dexterity is required.

Verbal Subtest of Vocabulary

The subtest of Vocabulary is administered as the fourth and last subtest of the WRIT. It is a subtest belonging to the subcategory of the Verbal IQ. The subjects have to define words presented orally by the examiner. This subtest requires that the subject understands the oral language and that it can give a verbal response. This subtest measures word knowledge, auditory processing skills, receptive and expressive language ability.

Scoring

On each subtest there is a generalized starting point concerning the complexity of the item determined by the age of the subject. If the subject completes its' first two items successfully the test can continue, otherwise the starting point is adjusted to a lower complexity. If the first item of the subject already has the lowest complexity and the subject fails to complete these two items correctly the administration of the test stops.

The raw score on each subtest is the sum of the items answered correctly which is converted to a standard score with the mean of 100 and a standard deviation of 15. By summing up the standard scores of the relating subtests the Verbal IQ and the Visual IQ are assessed. The General IQ is determined by converting the sum of the standard scores of the two subcategories. Additionally several tables are provided to convert and compare the results.

Validity and reliability

Reliability

Reliability coefficients were calculated using Cronbach's coefficient alpha. The average reliability coefficient results for the WRIT's General, Verbal and Visual IQ's are .95, .94 and .92 respectively which indicates homogeneity between the items and internal consistency. The average standard errors of measurement for General, Verbal and Visual IQ's are 4.7, 5.1 and 5.9 correspondingly. The average reliability coefficients for the individual sub-tests are .90 or above, except for Verbal Analogies (r= .84, SEM= 8.1). The adequacy of the reported reliability coefficients from these statistics are questionable because there was no age controlling as they were calculated across four age levels (4 to 5, 6 to 12, 13 to 18 and 19+).

Score stability was examined using data from the standardization sample.Test-retest coefficients for children are .90 for Visual IQ, .95 for Verbal IQ and .97 for General IQ. For adults are .92 for Visual IQ and .96 for both Verbal and General IQ. The composite scores show more variable and less acceptable results for both children and adults.

Intraclass correlation coefficients (ICC) were used to evaluate the extent of agreement and the conclusion was that little error is associated with scoring these sub-tests.

Validity

Statistical validity refers to the concept of how much a test is actually measuring what it is supposed to measure. As the WRIT is a shorter intelligence test than most other intelligence tests, a study by Shields et al. examined criterion-related, as well as secondary external and internal validity in the WRIT across different groups, such as gender, ethnicity and education level, to prove whether it is a valid method for testing intelligence. Internal validity was represented in the WRIT because the test consistently replicate the different subgroups of society, as well as external validity because it highly correlates with other tests, hence reproduce high generalization. To test criterion-related validity, the study evaluated the different outcomes of WRIT and the Wide Range Achievement Test (WRAT). The corresponding coefficients were statistically significant to verify the existing criterion-related validity in the WRIT. Results of the study by Canivez et al., in which they compared the WRIT with the Wechsler Abbreviated Scale of Intelligence (WASI) revealed that the WRIT is valid measurement regarding construct validity.

Advantages and disadvantages

Advantages

The WRIT has proven as highly valid and correlative with other sophisticated measurements of intelligence, such as the Wechsler Abbreviated Scale of Intelligence. Additionally, its short execution time (less than 30 min) while still maintaining high accuracy in the measured fields, makes it a favourable trait for many researchers.

Disadvantages

Like other intelligence measurements, the WRIT is unable to measure factors like emotional/ social intelligence.