Psychometric Properties of the Chinese Version of Everyday Cognition Scale (ECog) in Taiwanese Older Adults.

Background and objectives: The Everyday Cognition Scale (ECog) is widely employed for the subjective rating of functional activities of daily living in older adults. This study aimed to examine the psychometric properties of both informant-rated and self-rated ECog in Taiwanese older individuals to assess its applicability in this context.

Research design and methods: A total of 1,166 subjects, including older adults (n = 583) and their primary caregivers or family members (n = 583), were recruited. Both self-rated and informant-rated ECog assessments were administered twice within a 1-month period. The study evaluated internal consistency, test-retest reliability, random measurement error, discriminative validity, construct validity, and concurrent validity using the Mini-Mental State Examination (MMSE) as a gold standard.

Results: The informant-rated ECog demonstrated high internal consistency, acceptable to good test-retest reliability, small to moderate random measurement error, good discriminative validity, and moderate correlations with the MMSE. Additionally, a 7-factor model of the informant-rated ECog was supported. Conversely, the self-rated ECog exhibited high internal consistency, acceptable test-retest reliability, moderate to large random measurement error, adequate discriminative validity, and small correlations with the MMSE. Notably, only the domains of memory, verbal, planning, and organization were supported by a one-factor model.

Discussion and implications: The psychometric properties of the informant-rated ECog surpassed those of the self-rated ECog. However, the self-rated ECog is recommended as a supplementary tool for assessing individuals' awareness of their cognitive function, particularly in the domain of memory.