The influence of schooling on performance in the Mattis Dementia Rating Scale (DRS)

Studies have shown the influence of schooling on performance in the Dementia Rating Scale (DRS), suggesting that a single cut-off score is not appropriate for all groups of elderly people. Objectives To verify the influence of schooling on the DRS in a Brazilian elderly population. Methods The DRS was applied to 118 cognitively healthy controls and to 97 patients with mild probable Alzheimer's disease (AD). In order to analyze the influence of education, patients and controls were divided into four groups of schooling (GRSC): GRSC 1 with 1 to 4 years of schooling, GRSC 2 with 5 to 8 years of schooling, GRSC 3 with 9 to 11 years of schooling, and GRSC 4 with more than 11 years of schooling. Results In the intragroup analysis, the performance of controls within each schooling group was compared, revealing a significant difference on total score and the subscales Attention, I/P and Conceptualization. The same procedure was used for the AD patients and a significant difference was observed for total score and the subscales Attention, Construction, Conceptualization and Memory. In the intergroup analysis, the results on total DRS and for the I/P, Conceptualization and Memory subscales showed significant differences in GRSC 1, 2, 3 and 4. The Attention subscale showed differences in GRSC 3 and 4, and on the Construction subscale in GRSC 1 and 4. Conclusions The results highlight the importance of norms for the DRS in the Brazilian population that take into account the effects of schooling on the scores of this scale.