Bottom line: Age and educational level of patient need to be considered when interpreting results of MMSE.
Summary: Crum RM, et al. Population-based norms for the Mini-Mental State Examination by age and educational level. JAMA. 1993;269 (18):2386 -2391.
Study examined MMSE results for sample of over 18,000 adults. Data collected from surveys in several metropolitan areas in the US during 1980-84. RESULTS: Median score on the MMSE for people age 80 and over (n=950) was 25 compared to median score of 28 for the entire sample. In people age 80 and over median score for those with some high school education was 26 while the median score for those with at least some college experience was 29.
Kahle Wrobleski K, et al. Sensitivity and specificity of the mini-mental state examination for identifying dementia in the oldest-old: the 90+ study. J Am Geriatrics Soc. 2007; 55 (2) :284 -289.
This study compared findings of MMSE to combined findings from 3MS (from which MMSE derived) and neurological exams from trained examiners to document most sensitive and specific cutoffs for the MMSE in populations of people age 90 and older. RESULTS: Cutoffs for diagnosing dementia were ≤ 25 in those aged 90-93 years with college education or higher (82% sensitivity, 80% specificity), ≤ 24 in those aged 94-96 years with college education or higher (85% sensitivity, 80% specificity), and ≤ 22 in those aged ≥ 97 years with high school education or less (80% sensitivity, 76% specificity).
Both studies identified in DynaMed topic on Dementia Evaluation.