Correcting the 3MS for Bias Does Not Improve Accuracy When Screening for Cognitive Impairment or Dementia

ABSTRACT

We investigated the effects of correcting for demographic biases on the sensitivity and specificity of the Modified Mini Mental Status Exam (3MS) using a sample of English-speaking older adults (N = 8,901) from the Canadian Studies of Health and Aging. The sensitivity and specificity of the original 3MS were compared to the 3MS regression-adjusted for the influence of demographic variables and then to 3MS percentiles based on published normative data with age and education corrected cutoff scores. According to receiver operating characteristic curve analyses, the regression-adjusted 3MS was no more accurate than the original 3MS when screening for dementia, and it was less accurate when screening for cognitive impairment. The use of 3MS percentiles based on normative data with age and education corrected cut-off points were less accurate than the original 3MS when screening for both cognitive impairment and when screening for dementia.

ACKNOWLEDGEMENTS

M. E. O'Connell was aided in the manuscript preparation by a doctoral fellowship from the BC Medical Services Foundation. The Canadian Study of Health and Aging was funded by the Seniors’ Independence Research Program, through the National Health Research and Development Program (NHRDP) of Health Canada (project 6606-3954-MC(S)). Additional funding was provided by Pfizer Canada Incorporated through the Medical Research Council/Pharmaceutical Manufacturers Association of Canada Health Activity Program, NHRDP (project 6603-1417-302 (R)), Bayer Incorporated, the British Columbia Health Research Foundation (projects 38 (93-2) and 34 (96-1)). The study was coordinated through the University of Ottawa and the Division of Aging and Seniors, Health Canada. Finally, portions of this paper were presented at the meeting of the International Neuropsychological Society, Toronto, Ontario, February 14, 2002.