Operating characteristics of seven screens for dementia were compared across various groups for 795 persons who had received a criterion diagnostic evaluation. Area under the curve (AUC), based on receiver operating characteristics, was compared between and within scales as an indication of their efficiency. Differences in AUC were only 5% across all the scales for the entire sample, but increased to 11% across sociocultural groups and scales and to 20% across education groups and scales. Two scales (the Mini-Mental State Exam and the Short Portable Mental Status Questionnaire) misclassified most nondementias for the entire sample, and all scales misclassified most nondementias among persons with less than 5 years of education. Findings could support a recommendation that certain shorter scales be used because they perform as well as longer ones, are more consistent across cultural and educational groups, and can be more easily modified to improve performance in culturally diverse populations.