Confirmatory Factor Analysis of the Mattis Dementia Rating Scale in Patients With Alzheimer's Disease

Recent factor analyses of the Mattis Dementia Rating Scale (DRS; S. Mattis, 1973) have questioned the validity of its subscales, raising questions regarding their interpretation. This study examined the measurement structure of the standard DRS and of an abbreviated DRS form in a homogenous sample of 171 patients with Alzheimer's disease using (a) confirmatory factor analysis and (b) correlation of factors identified in the best fitting model with supplementary neuropsychological tests. We found confirmation of the validity of the Construction, Conceptualization, and Memory subscales associated with both the standard and abbreviated DRS. Correlations between these factors and supplementary neuropsychological measures supported the validity of the identified factors. The variability in DRS factor composition reported in previous studies appears to be related to sample heterogeneity, which is critically important to the resulting factor structure.