The ability to perform the instrumental activities of daily living (IADLs) is an important focus for the promotion of independent living in old age. If strategies to enable older people to remain in their own homes are to be developed, advances must be made in understanding the demands associated with IADLs. This paper reports on a study of how activity demands – the body postures, actions and hand functions involved in cooking, housework, laundering and shopping – relate to the capabilities of a sample of older people in Great Britain. Task data were analysed for 4,886 community-dwelling 55–93-year-olds who were enrolled in a follow-up survey to the 1996/97 Family Resources Survey. Logistic regression models were used to calculate adjusted odds ratios for associations between functional limitations and IADL difficulty. Attributable fraction estimates were also used to assess the population impact of the functional limitations. Comparable effect sizes were observed across activities for limitations in body postures (standing, reaching and bending/stooping), actions (lifting/lowering and holding/carrying) and hand functions. Most of the difficulties were attributable to limitations in body postures, primarily bending/stooping, whereas actions and hand functions accounted for much less difficulty. We present a matrix of the potential impact that design changes to alleviate each limitation would have on the ability to perform the activities studied. This can help to prioritise interventions aimed at supporting continued independent living.

Financial capacity is a complex instrumental activity of daily living critical to independent functioning of older adults and sensitive to impairment in patients with amnestic mild cognitive impairment (MCI) and Alzheimer’s disease (AD). However, little is known about the neurocognitive basis of financial impairment in dementia. We developed cognitive models of financial capacity in cognitively healthy older adults (n = 85) and patients with MCI (n = 113) and mild AD (n = 43). All participants were administered the Financial Capacity Instrument (FCI) and a neuropsychological test battery. Univariate correlation and multiple regression procedures were used to develop cognitive models of overall FCI performance across groups. The control model (R2 = .38) comprised (in order of entry) written arithmetic skills, delayed story recall, and simple visuomotor sequencing. The MCI model (R2 = .69) comprised written arithmetic skills, visuomotor sequencing and set alternation, and race. The AD model (R2 = .65) comprised written arithmetic skills, simple visuomotor sequencing, and immediate story recall. Written arithmetic skills (WRAT-3 Arithmetic) was the primary predictor across models, accounting for 27% (control model), 46% (AD model), and 55% (MCI model) of variance. Executive function and verbal memory were secondary model predictors. The results offer insight into the cognitive basis of financial capacity across the dementia spectrum of cognitive aging, MCI, and AD. (JINS, 2009, 15, 258–267.)