“TScores for Change”: An illustration of a regression approach to depicting change in clinical neuropsychology

Abstract

The interpretation of change scores in neuropsychological assessment is of increasing importance. In order to illustrate a regression approach to depicting change, 50 patients with chronic seizure disorders were assessed twice with the WAIS-R and the Wechsler Memory Scale-Revised over an average interval of 7.8 months. Regression analysis was employed to develop norms for change that were converted into standardized scores. These T Scores for Change were analyzed with a MANOVA to compare the effects of epilepsy surgery on cognition and memory in 50 right-temporal lobectomy and 47 left-temporal lobectomy patients. Significant group, test, and interaction effects were found. A profile of the T Scores for Change permitted quick and accurate appreciation of the major findings. The characteristics of the regression-derived T Score approach are compared with a recently suggested reliability approach.