Differential sensitivity of the Response Bias Scale (RBS) and MMPI-2 validity scales to memory complaints

Abstract

The MMPI-2 Response Bias Scale (RBS) is designed to detect response bias in forensic neuropsychological and disability assessment settings. Validation studies have demonstrated that the scale is sensitive to cognitive response bias as determined by failure on the Word Memory Test (WMT) and other symptom validity tests. Exaggerated memory complaints are a common feature of cognitive response bias. The present study was undertaken to determine the extent to which the RBS is sensitive to memory complaints and how it compares in this regard to other MMPI-2 validity scales and indices. This archival study used MMPI-2 and Memory Complaints Inventory (MCI) data from 1550 consecutive non-head-injury disability-related referrals to the first author's private practice. ANOVA results indicated significant increases in memory complaints across increasing RBS score ranges with large effect sizes. Regression analyses indicated that the RBS was a better predictor of the mean memory complaints score than the F, FB, and FP validity scales and the FBS. There was no correlation between the RBS and the CVLT, an objective measure of verbal memory. These findings suggest that elevated scores on the RBS are associated with over-reporting of memory problems, which provides further external validation of the RBS as a sensitive measure of cognitive response bias. Interpretive guidelines for the RBS are provided.