BACKGROUND:Several studies have identified moderate reliability and validity for the Mini-Mental State Examination (MMSE). Some researchers showed the superiority of other dementia screening tests over the MMSE considering the test quality criteria. The aim of this study was the evaluation of MMSE, especially in the area of geriatrics. PATIENTS AND METHODS:MMSE and DemTect were carried out with 154 geriatric patients: 71 persons without cognitive impairment and 83 persons without delirium showed cognitive impairments as revealed by the DemTect. In addition, we also applied the Clock-Drawing-Test (CDT), Reisberg-Scale, Geriatric Depression-Scale (GDS, 15-item version) and the Confusion-Assessment-Method (CAM). RESULTS:According to the multitrait-multimethod approach, MMSE's convergent and divergent validity is similar to that of the DemTect. Both tests correlate only moderately with Spearman (r = 0.609) and revealed similar results for dementia in 57.1 % of the patients. MMSE showed low reliability and moderate reliability (Cronbach's α = 0.82) when ten items with low discriminatory power were excluded from the total test score. Difficulty of all items is only moderate (p = 0.86) and only eight items of the MMSE showed good test difficulty. CONCLUSION:All in all, DemTect and MMSE are not interchangeable. The MMSE estimates the average cognitive impairment of patients as considerably less pronounced than the DemTect. MMSE is, thus, not an instrument that would be recommended for the identification of mild cognitive impairment. In this case, tests with higher reliability and validity should be used.