Validity and usefulness in four WIST studies recently reported in the journal

Four articles that reported studies that used the Whitaker Index of Schizophrenic Thinking (WIST) were published in the Journal of Clinical Psychology in early 1977. These articles are reviewed by the WIST's author in terms of necessary conditions for valid and useful studies of schizophrenic thinking. Two of the studies reported used the MMPI Sc Scale: one of them failed to note its limitations and used the WIST incorrectly; the other resulted in some useful data. The other two articles report ground-breaking investigations of schizophrenic thinking as conceptual rule-learning inability. They are viewed as providing a valuable new orientation in the study of schizophrenic thinking because they investigate the phenomena first-hand instead of relying simply on ordinary psychiatric diagnosis for a criterion. Some previously unpublished data on the WIST and intelligence relevant to all four studies are reported.