The performance of the Mini-Cog in a sample of low educational level elderly

OBJECTIVES: To study the criterion validity of the Mini-Cog in low educational level elderly. DESIGN: Cross-sectional and validation design. SETTING: Policlínica Piquet Carneiro, an outpatient unit of Rio de Janeiro State University Hospital, in Brazil. PARTICIPANTS: A convenient sample consisting of 306 individuals, 65 yrs or older, selected from April 8(th) to July 15(th), 2002. METHODS: All participants underwent comprehensive geriatric evaluations which included the Mini-Mental State Examination (MMSE) and the cognitive part of the Cambridge Examination for Mental Disorders of the Elderly – Revised (CAMCOG-R). They were classified as demented or non-demented (DSM-IV). A post-hoc analysis was performed on the data from the 3 word recall test of the MMSE, and the Clock Drawing Test from the CAMCOG-R, and respective scores were added and interpreted in accordance with the Mini-Cog protocol. RESULTS: 293 individuals completed all the study steps; 211 had 4 or less years of schooling and were included in the data analysis. 32% had dementia. Mini-Cog sensitivity and specificity was consistently low independently of the different cut-off points considered. The best performance was found at the cut-off point of 2/3 which yielded sensitivity and specificity of 60% and 65%, respectively. CONCLUSION: The Mini-Cog is not a good cognitive screening tool for individuals with less than five years of formal education.