Construct Validity of the MMPI-2 Restructured Clinical (RC) Scales: Reply to Rouse, Greene, Butcher, Nichols, and Williams

Abstract

Rouse, Greene, Butcher, Nichols, and Williams (2008) repeat two claims about the MMPI-2 Restructured (RC) scales. One asserts that the correlations of RC scales with parent Clinical scales are modest compared to the correlations with other existing MMPI-2 scales. In response, we reiterate that the RC scales were not meant to emulate the divergent and overlapping content of the Clinical scales. Instead, each represents a distinctive Clinical scale component. Although individually focused, the RC scales span collectively a wide range of content and used as multivariate predictors, account for most of the variance of each Clinical scale. Rouse et al. also claim that most RC scales are redundant with existing MMPI-2 scales, which they propose as substitutes (proxies). However, our analyses of Rouse et al.'s database and of our own data show that several of their proposed proxies are far less mutually distinguishable than are the RC scale counterparts. Furthermore, several Clinical scales are more successfully, and none are less successfully, accounted for by RC scales than by proxies. In response to Rouse et al.'s neglect of a body of empirical findings supporting the construct validity of the RC scales, we also review the relevant research literature.