Examination of Regression-based Discrepancy Scores for the RBANS in Detecting Cognitive Impairment from an Archival Sample

Objective: The purpose of this study was to evaluate the clinical utility of regression-based formulas for the RBANS indexes in screening for cognitive impairment. Method: A database of neuropsychological test results was created from archival records in a memory assessment clinic. The sample consisted of 83 individuals (37 males/46 females) with an average age of 70.1 (SD = 9.8) and 14.6 years of education (SD = 2.8). Diagnostic accuracy of regression-based predictions provided by Duff and Ramezani (2015) (Duff, K., & Ramezani, A. (2015). Regression-based normative formulae for the Repeatable Battery for the Assessment of Neuropsychological Status for older adults. Archives of Clinical Neuropsychology, 30, 600-604.) and from regression of WTAR standard score were examined via receiver operator characteristic curves. Preliminary generalizability investigation was completed using two additional datasets. Results: The WTAR was found to mediate the relationship between education and all RBANS index scores. The WTAR standard score was also found to contribute uniquely and significantly to the prediction of RBANS performance. Results of diagnostic accuracy analyses showed similar discriminating accuracy for all scores. There was limited support for using the WTAR over demographic variables alone in the estimation of RBANS performance; however, the WTAR was found to be more predictive than education, indicating potential clinical utility to using the word-reading score over just years of attained education. Conclusions: Use of these derived Total Scale score variants is recommended for the screening of cognitive impairment, particularly in individuals with superior or poor educational quality. Further research is required to evaluate the utility of these variations in more diverse samples.