Educational bias in the assessment of severe dementia: Brazilian cutoffs for severe Mini-Mental State Examination

Cognitive assessment in advanced stages of Alzheimer's disease (AD) is limited by the imprecision of most instruments. Objective: To determine objective cognitive responses in moderate and severe AD patients by way of the Severe Mini-Mental State Examination (SMMSE), and to correlate performances with Mini-Mental State Examination (MMSE) scores. Method: Consecutive outpatients in moderate and severe stages of AD (Clinical Dementia Rating 2.0 or 3.0) were evaluated and compared according to MMSE and SMMSE scores. Results: Overall 400 patients were included, 67.5% females, mean age 76.6 +/- 6.7 years-old. There was no significant impact of age or gender over MMSE or SMMSE scores. Mean schooling was 4.4 +/- 2.5 years, impacting SMMSE scores (p=0.008). Scores on MMSE and SMMSE were significantly correlated (F-ratio=690.6325, p<0.0001). Conclusion: The SMMSE is influenced by schooling, but not by age or gender, and is an accurate test for assessment of moderate and severe AD.