BACKGROUND/AIMS: The aim of this study was to assess whether combining the Rowland Universal Dementia Assessment Scale (RUDAS) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) could improve diagnostic accuracy when screening for dementia in an Arabic-speaking population with low levels of literacy.

METHODS: Based on data from 225 elderly participant and informant dyads, the screening performances of the two instruments were compared and three methods for combining them--'or', 'and' and 'weighted sum' rules--were assessed.

RESULTS: The 'weighted sum' method had a significantly better area under the curve value compared to the RUDAS used alone. The 'weighted sum' method and the 'and' rule had the highest specificity, while the 'or' rule had the best sensitivity.

CONCLUSION: Harnessing the RUDAS and IQCODE increased diagnostic accuracy when screening for dementia in this study population.