Are normative data from the 64-card version of the WCST comparable to the full WCST?

A retrospective study of Wisconsin Card Sorting Test (WCST) protocols was undertaken to determine the equivalence of the full WCST (Heaton, Chelune, Talley, Kay, & Curtiss, 1993) with the single-deck version of the WCST. Census-matched and demographically adjusted standardized scores for the full WCST were compared to the single deck WCST (WCST-64) with 332 clinical protocols using two methods. The comparisons were made using (1) standard scores derived from the new WCST-64 norms (Kongs, Thompson, Iverson, & Heaton, 2000) and from (2) WCST-64 percent scores standardized with the norms intended for the full WCST. The results revealed adequate correlations and accuracy scores for both census-based norms, although WCST-64 scores adjusted for demographic information were not comparable to full WCST scores. Furthermore, the number of cases in which estimated scores performed within an acceptable range of actual full-version WCST scores fell below acceptable ranges. Clinicians are encouraged to use data from the WCST-64 with caution.