RESUMEN
OBJECTIVES: We developed the Korean version of Severe Mini-Mental Status Examination (SMMSE-K) which is a brief cognitive test for the severely demented patients. METHODS: The translation was carried out keeping the basic structure of the English version Severe Mini-Mental Status Examination (SMMSE). The SMMSE-K, Korean version of Mini Mental State Examination (MMSE-KC), and Clinical Dementia Rating (CDR) were administered to 84 Alzheimer's disease (AD) patients and 36 cognitively normal elderly subjects. For evaluating the reliability of the SMMSE-K, Cronbach alpha coefficient, inter-rater reliability, and test-retest reliability were examined. For confirming the validity of the SMMSE-K, the correlations of the SMMSE-K with MMSE-KC and CDR were examined, and factor analysis was performed using principal component analysis with Varimax rotation. RESULTS: SMMSE-K was found to have a high internal consistency (Cronbach alpha coefficient=0.906, p<0.01), inter-rater reliability (Pearson correlation coefficient=0.980, p<0.01) and test-retest reliability (Pearson correlation coefficient=0.940, p<0.01). Performances on the SMMSE-K and MMSE-KC were found to correlate significantly in the subjects with CDR of 2 (Pearson correlation coefficient=0.827, p<0.001) and 3 (Pearson correlation coefficient=0.929, p<0.001). In the subjects with CDR of 3, the MMSE-KC showed a floor effect (2.93+/-3.21), whereas the SMMSE-K did not (11.00+/-8.48). Exploratory factor analysis yielded two factors (automatic informational processing, controlled informational processing) accounting for 76.1% of the total variance. CONCLUSION: The SMMSE-K was found to be a reliable and valid test for assessing the cognition of severely demented patients.