Factor analysis of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in a large sample of patients suspected of dementia.

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS; Randolph, 1998) is a popular neuropsychological assessment instrument with research supporting its clinical utility. However, the index structure of the RBANS was derived theoretically and was not based on factor analysis. The purpose of this study was to examine the factor structure in a large heterogeneous sample of patients referred for a dementia evaluation, using exploratory factor analysis. Results suggest a two-factor solution, the first factor defined predominantly as a memory factor and the second as predominantly a visuospatial factor. This study also sought to validate the obtained factors by examining their relationship with external neuropsychological variables. Correlations between the external variables provide further support for Factor 1 as a memory factor. Correlations with Factor 2 support its visuospatial features, although this factor may also be associated with other cognitive domains such as attention and general ability.

Dichotomous scoring of Trails B in patients referred for a dementia evaluation.

The Trail Making Test is a popular neuropsychological test and its interpretation has traditionally used time-based scores. This study examined an alternative approach to scoring that is simply based on the examinees' ability to complete the test. If an examinee is able to complete Trails B successfully, they are coded as "completers"; if not, they are coded as "noncompleters." To assess this approach to scoring Trails B, the performance of 97 diagnostically heterogeneous individuals referred for a dementia evaluation was examined. In this sample, 55 individuals successfully completed Trails B and 42 individuals were unable to complete it. Point-biserial correlations indicated a moderate-to-strong association (r(pb)=.73) between the Trails B completion variable and the Total Scale score of the Repeatable Battery for the Assessment of Neurological Status (RBANS), which was larger than the correlation between the Trails B time-based score and the RBANS Total Scale score (r(pb)=.60). As a screen for dementia status, Trails B completion showed a sensitivity of 69% and a specificity of 100% in this sample. These results suggest that dichotomous scoring of Trails B might provide a brief and clinically useful measure of dementia status.