RESUMO
While past research has demonstrated that low idea density (ID) scores from natural language samples correlate with late life risk for cognitive decline and Alzheimer's disease pathology, there are no published rubrics for collecting and analyzing language samples for idea density to verify or extend these findings into new settings. This unit outlines the history of ID research and findings, discusses issues with past rubrics, and then presents an operationalized method for the systematic measurement of ID in language samples, with an extensive manual available as a supplement to this unit (Analysis of Idea Density, AID). Finally, reliability statistics for this rubric in the context of dementia research on aging populations and verification that AID can replicate the significant association between ID and late-life cognition are presented.