Concurrent Validity of Performance-Based Measures of Daily Functioning with Cognitive Measures and Informant Reported Everyday Functioning

Abstract

Objective Despite the substantial need for reliable and valid assessment of functional ability in older adults, there is currently limited research on the emergence of early functional declines during prodromal dementia stages, such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI). This study uses novel performance-based assessments to characterize subtle, yet clinically meaningful, changes in functional ability. Method A sample of 93 older adults classified as cognitively unimpaired (CU; n = 30, Mage = 73.57 ± 6.66), SCD (n = 34, Mage = 72.56 ± 6.43), or MCI (n = 29, Mage = 78.28 ± 7.55) underwent neuropsychological testing along with an informant-rated daily functional skills measure (Assessment of Functional Capacity Interview). Participants also completed the Night Out Task (NOT), an open-ended performance-based measure of functional assessment, and the Financial Capacity Instrument–Short Form (FCI-SF) that assesses financial skills. Results The MCI group performed worse on the NOT and FCI-SF relative to SCD and CU. NOT and FCI scores were associated with measures of global cognitive function, executive function, processing speed, language and memory, and FCI-SF overall score was correlated with informant-rated functional ability. The NOT and FCI-SF were also predictive of informant-reported daily functioning over and above traditional cognitive data and demographics. Conclusions Performance-based measures of IADL may allow for earlier detection of subtle functional changes that might not be adequately captured by traditional measures. The measurement of early functional changes is an important global outcome to evaluate the efficacy of interventions in dementia research.