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ObjectiveThe objective of this study is to determine whether differential item functioning (DIF) due to cognitive status impacted three depressive symptoms measures commonly used with older adults.MethodsDifferential item functioning in depressive symptoms was assessed among participants (N = 3558) taking part in four longitudinal studies of cognitive aging, using the Geriatric Depression Scale, the Montgomery-Åsberg Depression Rating Scale, and the Center for Epidemiologic Studies Depression Scale. Participants were grouped by cognitive status using a general cognitive performance score derived from each study's neuropsychological battery and linked to a national average using a population-based survey representative of the US population. The Clinical Dementia Rating score was used as an alternate grouping variable in three of the studies.ResultsAlthough statistically significant DIF based on cognitive status was found for some depressive symptom items (e.g., items related to memory complaints, appetite loss, lack of energy, and mood), the effect of item bias on the total score for each scale was negligible.ConclusionsThe depressive symptoms scales in these four studies measured depression in the same way, regardless of cognitive status. This may reduce concerns about using these depression measures in cognitive aging research, as relationships between depression and cognitive decline are unlikely to have been due to item bias, at least in the ways that were measured in the datasets we considered.

ObjectivePrevious studies have identified differential item function (DIF) in depressive symptoms measures, but the impact of DIF has been rarely reported. Given the critical importance of depressive symptoms assessment among older adults, we examined whether DIF due to demographic characteristics resulted in salient score changes in commonly used measures.MethodsFour longitudinal studies of cognitive aging provided a sample size of 3754 older adults and included individuals both with and without a clinical diagnosis of major depression. Each study administered at least one of the following measures: the Center for Epidemiologic Studies Depression scale (20-item ordinal response or 10-item dichotomous response versions), the Geriatric Depression Scale, and the Montgomery-Åsberg Depression Rating Scale. Hybrid logistic regression-item response theory methods were used to examine the presence and impact of DIF due to age, sex, race/ethnicity, and years of education on the depressive symptoms items.ResultsAlthough statistically significant DIF due to demographic factors was present on several items, its cumulative impact on depressive symptoms scores was practically negligible.ConclusionsThe findings support substantive meaningfulness of previously reported demographic differences in depressive symptoms among older adults, showing that these individual differences were unlikely to have resulted from item bias attributable to demographic characteristics we examined.

Objective: To investigate whether self-efficacy moderates the association between self-rated memory and depressive symptoms in a large sample of older adults. The influence of self-efficacy and depressive symptoms on memory performance was also examined in a subsample of individuals who reported poor memory.Methods: Non-demented participants (n = 3766) were selected from the 2012 wave of the Health and Retirement Study. Depressive symptomatology was assessed with the 8-item Center for Epidemiologic Studies Depression Scale. A modified version of the Midlife Developmental Inventory Questionnaire was used as the measure of self-efficacy. Participants were asked to rate their memory presently on a five-point scale from Excellent (1) to Poor (5). Immediate memory and delayed memory (after a 5-min interval) were measured by the number of correct words recalled from a 10-item word list.Results: Multiple regression analyses revealed that negative ratings of memory were significantly associated with greater levels of depressive symptoms, with this effect being greatest in those with low levels of self-efficacy. Additionally, greater self-efficacy was associated with optimal objective memory performances but only when depressive symptoms were low in individuals who reported poor memory function (n = 1196).Conclusion: Self-efficacy moderates the relationship between self-rated memory function and depressive symptoms. Higher self-efficacy may buffer against the impact of subjective memory difficulty on one's mood and thereby mitigating the effect of depressive symptoms on memory. Interventions should focus on increasing perceived self-efficacy in older adults reporting poor memory function to potentially minimize memory impairment. [ABSTRACT FROM AUTHOR]

Objective The present study aimed to investigate whether cognitive reserve moderated the association between depressive symptoms and cognition, as well as brain volumes in a sample of older adults. Methods Non-demented participants ( n = 3484) were selected from the Washington Heights/Hamilton Heights Inwood Columbia Aging Project (Northern Manhattan). A subsample of these participants without dementia ( n = 703), who had brain imaging data, was also selected for a separate analysis. Depressive symptomatology was assessed with the 10-item Center for Epidemiologic Studies Depression Scale. Reading level and years of education were used as measures of cognitive reserve. Four distinct cognitive composite scores were calculated: executive function, memory, visual-spatial, and language. Results Multiple regression analysis revealed interaction effects between both measures of cognitive reserve and depressive symptoms on all the cognitive outcome measures except for visual-spatial ability. Those with greater reserve showed greater cognitive decrements than those with lower levels of reserve as depressive symptoms increased. A borderline interaction effect was revealed between reading level and depressive symptoms on total brain volumes. Those with lower reading scores showed greater volume loss as depressive symptoms increased than those with higher reading scores. Conclusions Our findings indicate that the association between late-life depressive symptoms and core aspects of cognition varies depending on one's level of cognitive reserve. Those that had greater levels of education and/or reading ability showed a greater decrease in memory, executive, and language performances as depressive symptoms increased than those with lower years of education and reading ability. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]