The aging population in the United States is becoming more racially and ethnically diverse than ever before. Health disparities have been well documented across diverse older adult populations, including evidence to suggest that there may be increased rates of Alzheimer's disease (AD) and related disorders among some groups. Researched aimed at understanding, preventing and ameliorating health disparities in AD is a major public health priority. However, to study and address these health disparities requires psychometrically sound and culturally appropriate assessment tools to sensitively measure early clinical signs associated with AD and to provide good outcome measures to track disease progression and response to treatment. The measurement properties of such assessment tools must be conceptually and psychometrically equivalent across diverse populations. With previous NIA funding (Farias, AG 0215111, AG 031252) we developed a novel questionnaire-based assessment tool (the Everyday Cognition scales (ECog) to measure very early limitations in everyday functions. Our work has shown that subtle changes in everyday functions, as measured by the ECog, can be used to identify older adults at increased risk for developing Mild Cognitive Impairment (MCI) and dementia. However, our most recent work has shown that the current version of the ECog is less sensitive to predicting disease progression in ethnic/racial minority subgroups (Latinos and African Americans) than it is in non-Latino Caucasians. Such findings provide clear rationale for the need to adapt and further refine this instrument to improve its utility as an early indicator of disease and as an outcome measure among diverse populations. The proposed study will utilize a multi-method (quantitative and qualitative) approach to evaluate and improve the measurement equivalence of the ECog among diverse older adult populations.
The aims of this study are twofold.
In Aim 1 we will utilize existing data from the University of California, Davis Alzheimer Disease Center's multiethnic longitudinal cohort to quantitatively evaluate which items of the ECog display evidence of poor measurement equivalence across three racial/ethnic groups (African Americans, Latinos, and non-Latino Caucasians) using sophisticated analytic methods. Informed by results of Aim 1, Aim 2 will employ well-established cognitive interviewing methods to further evaluate and identify the reasons why particular ECog items are problematic for specific racial/ethnic groups. For example, some items may not be readily understood as intended and/or some items may not be appropriate the cultural context and lifestyle of some groups. These items will be modified accordingly and a second wave of cognitive interviews will further evaluate item revisions. Completion of this study will provide the critical formative work to improve our ability to measure early changes in everyday function with comparable accuracy and precision across diverse older adult populations.
While the aging population in the U.S. is becoming increasingly racially/ethnically diverse, health disparities remain problematic, including evidence that rates of Alzheimer's disease (AD) are disproportionately high among some groups. Researched aimed at understanding, preventing and ameliorating these health disparities in AD is a major public health priority. However, this requires accurate and culturally sensitive assessment tools to measure early clinical signs of AD and to provide good outcome measures to track disease progression and response to treatment. The proposed study will utilize a multi-method (quantitative and qualitative) approach to improve the measurement of early everyday functional abilities associated with AD across diverse older adult populations.
