Awareness of functional ability in people with early‐stage dementia

Abstract

Objectives: Assessment of functional ability in people with early-stage dementia (PwD) is an important area of study because it forms part of the diagnostic process and may help in monitoring disease progression. Most researchers and clinicians rely on informant ratings rather than observing actual functional performance or employing self-ratings. There has however been little research to verify whether informant ratings of functioning are accurate, and there has been even less research investigating the accuracy of self-ratings of functional ability in PwD. No study has used the performancemonitoring metacognitive approach to investigate awareness of functional ability. Methods: Thirty-seven people with early-stage dementia completed an objective functional assessment and provided self-ratings before and after completing each section of the objective test. Informants provided ratings of functioning and burden. Scores were converted to percentages to allow for direct comparison. Results: Objectively assessed functional ability significantly correlated with self-ratings and informant ratings. Self-ratings did not correlate with informant ratings. For converted scores, self-ratings were more similar than informant ratings to the objectively assessed mean scores. Burden was unrelated to functional assessments after correcting for multiple comparisons. Conclusions: Self-rated functional ability was more accurate than informant ratings when compared with objectively assessed ability, with informants tending to significantly underestimate the functional ability of PwD. The findings call into question the likelihood that informants will provide accurate ratings of functional ability and suggests that self-ratings may offer a more accurate estimate of functional ability. Self-ratings made by PwD should be more widely employed in clinical and research settings.

The relationship between perceived functional difficulties and the ability to live well with mild‐to‐moderate dementia: Findings from the IDEAL programme

“…An alternative FAQ cut-off score of 9 has been recommended as indicative of impairment 44 and is used primarily in North America; 50 thus, level 3 included those who scored 6 to 9. The remaining three groups reflect equal score ranges comprising 8 points each: level 4 (10-17), level 5 (18)(19)(20)(21)(22)(23)(24)(25), and level 6 (26)(27)(28)(29)(30)(31)(32)(33). Participants with dementia who had no informant participating in the study were included in the analyses using FAQ-S ratings but not in the analyses using FAQ-I ratings.…”

“…2,11,[27][28][29][30][31][32] Functional ability has also been investigated concerning self-rated and informant-rated QoL in dementia, with functional difficulties leading to poorer QoL outcomes. 2,11,[27][28][29][30][31][32] Functional ability has also been investigated concerning self-rated and informant-rated QoL in dementia, with functional difficulties leading to poorer QoL outcomes.…”

“…39 In contrast, for assessing functional ability, informant ratings are the primary method of assessment, 2,41 often assumed to be the more accurate, with cognitive decline precluding the possibility of obtaining valid selfratings. 32,46 We recently found that, when comparing self-ratings and informant ratings of functional ability with objective performance, people with mildto-moderate dementia were able to more accurately appraise their functional ability than their informants, with the latter typically underestimating ability. 32,46 We recently found that, when comparing self-ratings and informant ratings of functional ability with objective performance, people with mildto-moderate dementia were able to more accurately appraise their functional ability than their informants, with the latter typically underestimating ability.…”

“…In people with dementia, reduced functional ability is consistently associated with higher depression, increased age, lower education, and poorer cognitive status. 2,11,[27][28][29][30][31][32] Functional ability has also been investigated concerning self-rated and informant-rated QoL in dementia, with functional difficulties leading to poorer QoL outcomes. [33][34][35][36][37][38][39] Investigating QoL in people with mild-to-moderate dementia typically involves use of either self-ratings or informant ratings, 40 and it is generally accepted that people with mild-to-moderate dementia can provide valid self-ratings.…”

“…28,[42][43][44] However, higher carer stress is consistently associated with lower informant-rated functional ability 45,46 whereas carer stress is typically unrelated to objectively assessed functional performance. 32,46 We recently found that, when comparing self-ratings and informant ratings of functional ability with objective performance, people with mildto-moderate dementia were able to more accurately appraise their functional ability than their informants, with the latter typically underestimating ability. 32 In view of this finding, it is important to consider how subjective perceptions of functional ability relate to both self-rated and informant-rated living well scores.…”