The Wisconsin Card Sorting Test (WCST) was developed to assess abstract reasoning and the ability to shift cognitive strategies in response to changing environmental contingencies (Heaton, Chelune, Talley, Kay, & Curtiss, 1993). It was considered a measure of executive function, such as impulsive responding inhibition, problem solving, and working memory (Bulter, Retzlaff, & Vanderpioeg, 1991).
The Wisconsin Card Sorting Test-computer Version 4 (WCST-CV4) (Heaton, 2005) is a computerized version. It consists of 128 response cards representing figures of varying forms, colors and numbers. The subject was asked to match the response cards with the stimulus card which the subject thought it matchers. Subjects were neither told the correct sorting principle, nor informed of shifting the sorting categories (color, form, and number) during the test. As long as the subject had achieved 10 consecutive “correct” matches to the current sorting category, the sorting principle was changed, and the subject had to switch the sorting rule from previous category to another one. The test ended when the subject had successfully completed six categories or the 128 response cards had been used (Heaton, et al., 1993).
There are 16 indices in the WCST: number of trials administered, total number correct, total number of errors, percent errors, perseverative responses, percent perseverative responses, perseverative errors, percent perseverative errors, nonperseverative errors, percent nonperseverative errors, conceptual level responses, percent conceptual level responses, number of categories completer, trials to complete first category, failure to maintain set, and learning to learn (Heaton, et al., 1993).
Perseverative responses. When the subject persists in responding to a characteristic that is not correct, this kind of response is identified “perseverative”. Count the number of items which represented perseverative performance.
Perseverative errors. Count the number of items that are incorrect and represent perseverative performance.
Nonperseverative errors. Count the number of items that are incorrect and do not represent perseverative performance. The sum of the raw score of perseverative errors and the raw score of nonperseverative errors should equal to the raw score of total number of errors.
Conceptual level responses. It is defined as consecutive correct responses occurring in runs of three or more. It is assumed that some insight into the correct sorting strategy is required in order to make three or more consecutive correct matches and that a correct series of this length would be unlikely to happen by chance.
Percent errors, percent perseverative responses, percent perseverative errors, percent nonperseverative errors, and percent conceptual level responses. These scores are calculated respectively by dividing the raw score of number of trails administered, multiplying the result by 100, and rounding to the nearest whole number.
Number of categories completed. The number of categories completed is simply the number of categories that a subject successfully completes. Scores can range from 0-6.
Trials to complete first category. The total number of trails to successfully complete the first category gives an indication of initial conceptualization before shifting to next category.
Failure to maintain set. A failure to maintain set occurs when a subject makes five or more consecutive correct matches, but then the subject makes an error before successfully completing the category.
Learning to learn. It reflects the subject’s average change in conceptual efficiency across the consecutive categories of the WCST. A positive score of learning to learn indicates improved efficiency across consecutive categories. The reason of a positive score may be learning. The score compares with the appropriate reference group to identify the relative performance.
The following indices are analyzed: total number correct (TNC), perseverative responses (PR), perseverative errors (PE), nonperseverative errors (NPE), conceptual level responses (CLR), number of categories completed (NCC), trails to complete first category (TCC), and failure to maintain set (FMS). The index of total errors is not included, because it is a linear combination of PE and NPE. The indices of the percentage scores are not used, because the reliabilities of these percent scores are lower than those of their respective basic scores The index of learning to learn is not use, because of missing values for many patients who achieved fewer than three categories (Heaton, et al., 1993; Su, Wuang, Chang, Guo, & Kwan, 2006).
Bulter, M., Retzlaff, P., & Vanderpioeg, R. (1991). Neuropsychological test usage. Professional Psychology: Research and Practice, 22, 510-521.
Heaton, R. K. (2005). Wisconsin Card Sorting Test: Computer Version 4 research edition. Lutz, FL: Psychological Assessment Resources, Inc.
Heaton, R. K., Chelune, G. J., Talley, J. L., Kay, G. G., & Curtiss, G. (1993). Wisconsin Card Sorting Test manual revised and expanded. Lutz, FL: Psychological Assessment Resources, Inc.
Su, C.-Y., Wuang, Y.-P., Chang, J.-K., Guo, N.-K., & Kwan, A.-L. (2006). Wisconsin Card Sorting Test performance after putaminal hemorrhagic stroke. The Kaohsiung Journal of Medical Sciences, 22(2), 75-84.