Comprehensive Evaluation of the Functional Activities Questionnaire (FAQ) and Its Reliability and Validity

Abstract

The Functional Activities Questionnaire (FAQ) is a collateral-report measure of difficulties in activities of daily living. Despite its widespread use, psychometric analyses have been limited in scope, piecemeal across samples, and limited primarily to classical test theory. This article consolidated and expanded psychometric analyses using tools from generalizability and item response theories among 27,916 individuals from the National Alzheimer’s Coordinating Center database who completed the FAQ. Reliability was evaluated with internal consistency, test–retest, and generalizability analyses. Validity was assessed via convergence with neurocognitive measures, classification accuracy with impairment stage, and confirmatory factor and item response theory analyses. Demographics did not impact scores and there was strong evidence for reliability (0.52-0.95), though coefficients were attenuated when restricted in range to diagnostic groups (e.g., normal cognition). There were strong correlations with neurocognitive measures ( rs: −.30 to −.59), strong classification accuracy (areas under the curve: .81-.99), and a single-factor model had excellent fit. All items evidenced strong item response theory discrimination and provided significant information regarding functional disability, albeit within a relatively restricted range. The FAQ is a reliable and valid measure of activities of daily living concerns for use in clinical/research settings. It best assesses mild levels of functional difficulty, which is helpful in distinguishing normal cognition from mild cognitive impairment and dementia.

Cognitive screening with functional assessment improves diagnostic accuracy and attenuates bias

“…The demographically corrected MTMM approach yielded the most equivalent diagnostic accuracy across NHW and BA groups, which aligns with research demonstrating demographic correction improves classification accuracy based on CS, 14 and clinical staging derived from the FAQ is relatively robust against demographic effects. 23 The ability of two time-and cost-efficient tools to reduce biases in classification accuracy across diverse groups is notable given striking disparities in timely diagnosis and access to care. 2 With the growing availability of large datasets, there is increasing use of advanced algorithms for data modeling and prediction.…”

“…The FAQ has robust clinimetric properties and classification accuracy for detecting MCI/dementia. 23 Finally, participants had the Clinical Dementia Rating (CDR Dementia Staging Instrument 24 , 25 ), a valid and reliable semi‐structured interview of cognitive and functional status, to stage participants’ level of impairment into one of five diagnostic categories (i.e., CU, questionable/MCI, mild dementia, moderate dementia, and severe dementia). The CDR is rated independently from the MoCA and FAQ and, for this study, dementia severities were collapsed consistent with the CU–MCI–dementia staging.…”

“…FAQ items are rated on a 4‐point ordinal scale, and total scores range from 0 to 30 with higher scores indicating greater functional impairment. The FAQ has robust clinimetric properties and classification accuracy for detecting MCI/dementia 23 . Finally, participants had the Clinical Dementia Rating (CDR Dementia Staging Instrument 24,25 ), a valid and reliable semi‐structured interview of cognitive and functional status, to stage participants’ level of impairment into one of five diagnostic categories (i.e., CU, questionable/MCI, mild dementia, moderate dementia, and severe dementia).…”

Instrumental Activities of Daily Living Scales to Detect Cognitive Impairment and Dementia in Low- and Middle-Income Countries: A Systematic Review

“…In contrast, there is significant evidence that tools which have been translated and adapted from Western high-income countries are feasible and acceptable to use in South America. For example, the FAQ shows acceptableexcellent diagnostic accuracy in Brazil [20][21][22] and is one of the most commonly used IADL scales worldwide [41]. This lends more confidence to the generalisability of translated scales on a global scale, but these tools have not been investigated in Africa or South Asian countries which may have unique cultural expectations, as discussed previously.…”

“…Only two studies explicitly included both urban and rural communities, highlighting a significant gap that should be addressed through future studies [29,31]. [20][21][22][41][42][43]. Several studies also excluded people with physical impairments or other neurological conditions [12, 13, 16, 17, 22-25, 34, 44], limiting our understanding of how IADL tools might distinguish dementia from other disorders in a population-level cohort.…”