Caregivers' judgments of the functional abilities of the Alzheimer's disease patient: impact of caregivers' depression and perceived burden.

Research has demonstrated that caregivers of cognitively impaired patients may misjudge aspects of the patient's functional capacities. The nature and directions of these relationships are not well understood, however. Further, the effects that depression and perceived caregiver burden have on the caregivers' ability to render accurate judgments of patient's functional abilities have not been addressed. In this study, the primary caregivers of 128 patients with Alzheimer's disease (AD) were administered a questionnaire regarding the patients' functional capacities. These judgments were subsequently compared to actual functional performance of AD patients on an extended version of the Direct Assessment of Functional Status scale administered in the patients' home environment. A significant proportion of caregivers overestimated AD patients' functional performance in telling time, counting currency, making change for a purchase, brushing teeth, and using eating utensils. Further analyses revealed that self-reported depression, but not perceived burden, was related to the type of caregiver bias errors observed.