Test structure
Respondents are required to sort numbered response cards according to different principles and to alter their approach during test administration. To complete the task, clients should have normal or corrected vision and hearing sufficient to adequately comprehend the instructions and to visually discriminate the stimulus parameters.
Administration
- Administration should take place in a quiet room with illumination adequate for viewing the WCST stimuli.
- A table or desk and two chairs, one for the examiner and one for the subject are required.
- A clipboard to hold the record booklet is also desirable in order to shield the record booklet from the client’s view.
- Prior to administration, the examiner should inspect the WCST response card decks to ensure that cards are properly oriented and are in proper numerical sequence within each deck.
Scoring and reporting
- The subject is presented with four key cards and two decks of 64 response cards, but not told in what way the response cards should match.
- Each response a client makes can be thought of as occurring in three separate dimensions and, thus, is evaluated on each. These dimensions are: Correct-Incorrect, Ambiguous-Unambiguous, and perseverative-nonperseverative.
- Successful performance on the WCST requires a client to first determine the correct sorting principle on the basis of examiner feedback and then to maintain this sorting principle or set (e.g. color) across changing stimulus.
Reliability, validity, and norms
- Raw score to normalized standard, percentile, and T-score conversions are provided.
- Normative data were derived from a sample of 899 normal children, adolescents, and adults.
- The WCST has been used extensively in clinical and research applications as a measure of executive function.
- Clinical groups investigated have included subjects with focal and diffuse brain damage, seizure disorders, Parkinson’s disease, multiple Sclerosis, and psychiatric disturbances such as schizophrenia.
- Interscorer agreement was found to be excellent for both the standard scoring instructions and for standard scoring instructions with supplemental material.