Health-Related Quality of Life in Community-Dwelling Older People with Cognitive Impairment: EQ-5D-3L Measurement Properties

Abstract

Background:

Assessing quality of life (QoL) in older people with cognitive impairment is a challenge. There is no consensus on the best tool, but a short, user-friendly scale is advised.

Objective:

This study aimed to assess the psychometric properties of the self-reported and generic EQ-5D (including the EQ index and EQ visual analog scale [VAS]) in community-dwelling older adults with cognitive impairment.

Methods:

Cross-sectional study analyzing the feasibility, acceptability, reliability, and validity of the EQ-5D based on 188 self-administered questionnaires in a sample of community-dwelling older adults with Mini-Mental State Examination (MMSE) scores of 10 to 24 points.

Results:

The EQ index was 0.69 (±0.27) and the EQ VAS was 63.8 (±28.54). Adequate measurement properties were found in acceptability and feasibility. Cronbach’s alpha was 0.69. Good validity was observed in the correlation of each dimension of the EQ-5D with geriatric assessment scales. Higher validity was observed for the EQ index compared to the EQ VAS.

Conclusion:

The EQ-5D scale could be a good tool for assessing health-related QoL in community-dwelling older adults with cognitive impairment, though it is necessary to assess the dimensions and the EQ index.

Keywords

Cognitive impairment community-dwelling measurement older people quality of life

INTRODUCTION

The increasing interest in measuring quality of life (QoL) in older people resides in the need to understand the effectiveness of interventions in prevention and health promotion programs. Resource management is subject to constant innovations, so the implementation of preventive strategies at different levels should be evaluated. Interventions targeted at older people should be assessed for their cost-effectiveness in order to identify those with the strongest capacity to improve QoL and provide value for money. Indeed, assessing QoL as an economic measure of interventions is a widely used tactic in adults, though less so in older people [1].

Assessing the effect of health interventions on QoL could provide more consistent results than analyzing disease outcomes due to the high comorbidity presented by this population [2]. Quality of life is defined as “an individual’s perceptions of their position in life, in the context of the culture and value systems in which they live, and in relation to their goals, expectations, standards and concerns” [3]. Health-related quality of life (HRQoL) can be defined as “how well a person functions in their life and his or her perceived wellbeing in physical, mental, and social domains of health.”

Yet, measuring QoL can be difficult because the concept itself is complex. Assessment is characterized by its multidimensionality, with both objective and subjective measures, and multivariate evaluation designs are based on the person and their environment as well as consideration of the systems perspective, which encompasses the multiple environments that impact on the person and the increasing participation of people with cognitive disability [4].

Different studies have observed that community-dwelling older adults have shown higher HRQoL than those in institutions, mainly due to lower comorbidity and dependency along with greater socialization [5 –7]. The most important factors mentioned in the literature to improve HRQoL in community-dwelling older adults are: cohabitation at home, socialization and social support, independence, and physical activity, while the factors that have a negative influence are mainly comorbidities that impair function, pain, depression, falls, frailty, sarcopenia, and dementia [8 –12].

Assessing self-perceived HRQoL in older people with dementia is generally considered challenging. In advanced stages, this syndrome can affect the reliability of the data collected [13]. Although there are studies showing differences between self-reported assessment by the patient with dementia and that by the family caregiver [14], a fact that has led to discrepant perspectives on the desirability of using a proxy, like the primary caregiver or clinicians, versus directly obtaining information from the person being assessed—which is always preferable when conditions allow [15]. Although some authors defend the use of proxies, pointing to the good psychometric properties achieved, factors like emotional state or caregiver fatigue can negatively affect a HRQoL assessment [16]. There is a dearth of literature that analyzes HRQoL according to the severity of the dementia or other factors that negatively influence HRQoL, independently of the severity of the condition, for example a person’s knowledge that they have cognitive impairment [13].

There are different tools for assessing HRQoL in older people, both generic and specific to different pathologies, including dementia. However, there is a need for further research in order to know the validity of dementia-specific instruments in different groups and areas [17, 18]. Moreover, the diversity of the tools makes it difficult to standardize an instrument [19] and compare the results of different studies in the literature [1]. Using generic scales in populations with a specific pathology would enable comparison of interventions in different populations and settings, but it is necessary to know their properties in the populations under study.

In that regard, the EQ5D has been shown to be a good instrument for assessing HRQoL in community-dwelling older adults [20] and in institutionalized people with cognitive impairment [21]. This scale is a short and easy-to-use, and it is widely applied in community-dwelling older adults [20, 22]. Diaz-Redondo et al. [23] analyzed the psychometric properties of the proxy-rated EQ-5D, showing it to be a valid alternative for assessing quality of life in institutionalized older people with dementia. Ankri et al. [16] also point to the possibility of using the EQ-5D for people with dementia, although different authors indicate the need for more studies that analyze both its properties for assessing HRQoL according to the severity of the dementia and its validity in the absence of a gold standard [16, 24].

The aim of our study was to assess the psychometric properties of the EQ-5D in community-dwelling older adults with cognitive impairment.

MATERIALS AND METHODS

Study design and participants

A cross-sectional study was carried out from 1 January 2020 to 13 March 2020. The inclusion criteria were: participants aged 70 years or older; cognitive impairment assessed by family physician after cognitive evaluation with the Mini-Mental State Examination (MMSE), with Cronbach’s alpha 0.90 and a score between 10 to 24, indicating cognitive impairment [25, 26]; living independently in the province of Valencia (Spain) and with the ability to read and write. Exclusion criteria were: refusal to participate in the study, serious psychiatric problems (severe depression subjected to treatment or acute psychosis), or severe cognitive impairment (diagnosed previously by a physician), the existence of associated disease conditions resulting in a life expectancy of under 6 months, blindness, or deafness.

Sample size description

A total of 361,575 community-dwelling older adults province-wide were included in the population census of 2019. The sample size was calculated based on this census to estimate a 18.5% incidence of older adults with mild-severe cognitive impairment [27], with an alpha error of 5%, precision of 3%, and a statistical power of 95%. The final minimum sample of participants required was 165.

In order to use an adequate sampling frame, we decided to recruit participants over a period of two months. The assessment was carried out in primary care centers of Valencia. All people who showed their willingness to participate and who met the inclusion criteria were included. To encourage participation, posters were hung and flyers distributed; open information sessions were also held for older individuals interested in participating in the study. In addition, volunteers signed up on a list in each center, and their data were recorded using alphanumeric codes identifying the center and the individual.

Data collection and quality of life assessment

Personalized interviews were undertaken with each participant to perform the geriatric assessment and collect data on age and sex as well as cognitive, functional, and emotional variables. Four nurses with at least five years’ experience in primary health care centers and nursing homes were in charge of this task, which was part of their routine clinical practice; they were not otherwise involved in the study. All assessments were performed in the morning, after breakfast and before lunch, between 9 am and 12 pm.

Health-related quality of life was assessed using the EQ-5D visual analog scale (VAS) and, the EQ-5D index according to the parameters of the Spanish population. In order to provide information on the three aspects of HRQoL, the EQ-5D-3L (Levels) was used. First, its descriptive system assesses the level of impairment in each of the five dimensions included in the scale: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has three levels of impairment: no problems (level 1), some problems (level 2), and extreme problems (level 3). Second, the descriptive response from the EQ-5D can be adapted into an index score. The score ranges from less than 0 to 1 (where 0 is a health state equivalent to death and negative values are worse than death) and 1 is the most positive score (the maximum level of perceived HRQoL according to the five dimensions included on the scale). Finally, the EQ VAS score was obtained by asking the patients to rate their health on a 20 cm vertical scale. The scale ranges from 0–100, where 0 is the ‘worst imaginable health’ and 100 is the ‘best imaginable health’ [22].

The functional and emotional assessment tools were the Barthel Index Basic Activity of Daily Living, the Tinetti Balance and Gait Scale, the Yesavage Geriatric Depression Scale (GDS), the Lawton Instrumental Activity of Daily Living Scale (IADL), and the VAS pain. In the present study they were used to obtain the information and complete an individualized geriatric assessment for each participant.

The Barthel Index (BI) is a scoring technique that measures the patient’s performance in 10 activities of daily life. The items can be divided into a group that is related to self-care (feeding, grooming, bathing, dressing, bowel and bladder care, and toilet use) and a group related to mobility (ambulation, transfers, and stair climbing). The total score ranges from 0 (totally dependent) to 100 (totally independent); scores are awarded in multiples of 5 [28]. The BI takes may vary depending on participants’ tolerance and abilities to self-report for 2 to 5 min and to submit to direct observation for 20 min.

The Tinetti scale has a gait score and a balance score. It uses a 3-point ordinal scale of 0, 1 and 2. Gait is scored over 12 and balance is scored over 16 for a total of 28 possible points. A total score of less than 19 points indicates a fivefold increased risk of falls, so the lower the total score, the higher the risk of falling [29]. The time to complete is 10 to 15 min.

A Short Form GDS consisted of 15 questions. Ten of the 15 items indicate the presence of depression when answered positively, while the other 5 (question numbers 1, 5, 7, 11, 13) are indicative of depression when answered negatively. Scores of 0 to 4 are considered normal, depending on age, education, and complaints; 5 to 8 indicate mild depression; 9 to 11 indicate moderate depression; and 12 to 15 indicate severe depression [30]. This form can be completed in approximately 5 to 7 min, making it ideal for people who are easily fatigued or are limited in their ability to concentrate for longer periods of time. The time to complete can be up to 20 min, depending on the person’s emotional state.

The Lawton IADL scale measures people’s ability to perform eight activities (using the telephone, shopping for groceries, food preparation, housekeeping, laundering, self-medicating, transportation, and managing finances). The total score ranges from 0 (totally dependent) to 8 (totally independent) [31]. The Lawton IADL scale takes 10 to 15 min to administer and contains eight items, with a summary score from 0 (low function) to 8 (high function). The time to complete is 2 to 5 min if self-reported.

The VAS pain scale [11] is a continuous scale comprised of a horizontal or vertical line, usually 10 cm in length. For pain intensity, the scale goes from 0 (indicating no pain) to 10 (worst imaginable pain) [32]. The time to complete is 2 min.

Ethics

All participants gave their informed consent for inclusion before they enrolled in the study. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Clinical Research Ethics Committee of the University of Valencia (Valencia, Spain; Project identification code 1060896).

Measurement properties

We analyzed the main measurement properties of the QoL instruments, including feasibility, acceptability, reliability, and construct validity, according to the criteria set out in Table 1. As there is no gold-standard measure for QoL, criterion validity was not appraised [33].

Table 1

Measurement properties of QoL instrument

Property	Criteria
Feasibility	Percentage of missing data (should be <10%)
	Percentage of computable data (should be >95%)
	Mean, median, and standard deviation similar across items (15% maximum divergence)
Acceptability	Asymmetry and kurtosis should oscillate between –1 and 1
	Floor and ceiling effect (percentage of scores in the lower and upper extremes should be <15%)
	Internal consistency: Cronbach's alpha (acceptable values ≥0.7)
Reliability	Stability of the measure: ICC (EQ index and EQ VAS, one-way, random-effects model; acceptable values were ≥0.7)
	Convergence: a) correlation between EQ index and VAS, and b) correlation between dimensions of EQ and assessment scales
Validity	Divergence: correlation between EQ VAS and assessment scales (should be low; R≤0.30)
	Internal: R² of two linear regressions between EQ index and assessment scales and EQ VAS and assessment scales

ICC, intraclass correlation coefficient; EQ index, EuroQol 5 Dimensions 3 Levels Index; EQ VAS, EuroQol Visual Analog Scale.

In order to determine the feasibility of the instrument under normal conditions, we analyzed the percentage of missing data [34]. The adequate distribution of scores among the sample indicates the acceptability [35], including measures of central tendency and floor and ceiling effect [36, 37].

To analyze reliability, we assessed Cronbach’s alpha for internal consistency and the stability of the measure [31]; and the intraclass correlation coefficient (ICC) to evaluate the stability between the EQ index and the EQ VAS [38].

Validity convergence determines the relationship of the scale with other measures assessing the same construct. We used the correlation coefficient (Pearson’s or Spearman’s), considering high correlation, R≥0.50; moderate, R of 0.35 to 0.49; and weak, R≤34, which was assessed according to Feeny et al.’s criteria [39]. Moreover, the correlation between dimensions of EQ and assessment scales was analyzed.

The results of each EQ-5D domain were rated from 1 (no problems) to 3 (extreme problems) and compared to the scales assessing the same domains. The Tinetti scale (gait and balance) functional score refers to domain 1 (mobility) in the EQ-5D; the Barthel scale score (ADL) refers to domain 2 (self-care); the Lawton scale (IADL), to domain 3 (usual activities); the GDS (depression symptoms), to domain 4 (anxiety-depression); and the VAS pain scale, to domain 5 (pain).

In order to relate the quantitative scales (Tinetti, Barthel, Lawton, GDS, and VAS pain) with the EQ-5D domains, we classified the validated scores of each scale into three categories, corresponding to the EQ-5D levels 1 to 3. Thus, for self-care, the distribution on the Barthel Index was: level 1, 65 to 100 points; level 2, 35 to 60 points; and level 3, 0 to 30 points for mobility. The Tinetti scores were categorized as follows: level 1 (no problems), 20 to 28 points; level 2 (some problems), 10 to 19 points; and level 3 (extreme problems), 0 to 9 points. For anxiety/depression, the GDS scores were transformed as: level 1, 0 to 4 points; level 2, 5 to 10 points; and level 3, 11 to 15 points. For usual activities, Lawton scores were ordered as: level 1, 6 to 8 points; level 2, 3 to 5 points; and level 3, 0 to 2 points. For pain/discomfort, VAS scores were distributed into: level 1, 0 to 3 points; level 2, 4 to 7 points; and level 3, 8 to 10 points.

Divergent validity refers to the association between the scale and other measures that assess different constructs [40]; only the EQ VAS was analyzed since the EQ index is obtained from the computation of the dimensions comparable to the assessment scales. To assess internal validity, we performed two linear regressions with the EQ index and the EQ VAS. In order to understand the relationship between the variables included and the value of R², the categorized scales were included into the three levels equivalent to the dimensions of the EQ-5D-3L (Table 1).

Statistical analysis

The variables are reported as proportions and/or means and standard deviation (SD). The Kolmogorov-Smirnov test was used to assess normality, and the Levene test was applied to explore homogeneity of variances for continuous variables (age, MMSE, EQ-5D VAS and EQ-5D index, Barthel Index, Tinetti Index, GDS, Lawton Index, and VAS pain). There were no significant outliers. The data met the main assumptions of normality, so the t-test for independent samples was used to compare means. The chi-squared test was used to compare categorical variables (gender).

RESULTS

Of the 361 people initially evaluated for eligibility, 47.9% (n = 173) were excluded: 6.9% (n = 12) declined to participate, 81.5% (n = 141) did not meet the selection criteria, and 11.5% (n = 20) were not capable of responding to the items on the questionnaire. The final study sample thus comprised 188 participants (52.1%) with a predominance of women (64.9%; n = 122). The participants presented high functionality in both IADL and gait and balance, as well as a low level of depressive symptoms and pain (Table 2).

Table 2

Baseline participant characteristics (n = 188)

Variables	Mean (SD)	Min	Max
Age, y	79.19 (5.18)	70	95
MMSE, points (0–30)	21.18 (3.17)	10	24
Barthel Index, points (0–100)	88.48 (17.27)	0	100
Lawton Index, points (0–8)	6.24 (2.06)	0	8
Tinetti Index, points (0–28)	21.26 (6.84)	0	28
GDS, points (0–15)	3.97 (3.56)	2	15
VAS pain, points (0–10)	3.07 (2.86)	0	10

GDS, Geriatric Depression Scale; MMSE, Mini-Mental State Examination; SD, standard deviation; VAS, visual analog scale.

The sample showed good HRQoL, as assessed by the EQ-5D, with over 60% of the participants showing no problems in the dimensions of mobility, self-care, usual activities, or pain. The anxiety scores showed a larger proportion of participants with some or extreme problems (Fig. 1). Participants presented good QoL scores on both the EQ index and the EQ VAS, with mean index and VAS scores hovering around 60% to 70% of the maximum possible QoL (Table 3).

Fig. 1

Distribution of responses on the EuroQol dimensions.

Table 3

Feasibility and acceptability properties of the EQ index and EQ VAS (n = 188)

	EQ index	EQ VAS
Mean	0.69	63.8
Standard deviation	0.27^*	28.54^*
Median	0.74	70
Asymmetry	–0.49	–0.76
Kurtosis	–0.75	–0.23
Ceiling	29.7^†	14.6^†
Floor	5.5	4.8

^*Divergence >15%; ^deg effect >10%.

Psychometric properties: Feasibility and acceptability

There were few missing data, and just 9.6% (n = 20) of the 208 older adults who were willing to participate were unable to respond to the questionnaire items, so feasibility was adequate. All data were computable.

After analyzing the items for acceptability, similar values were observed in the mean and median, while asymmetry and kurtosis were within the recommended bounds. On the contrary, a ceiling effect was observed in both EQ index and EQ VAS, and the SD diverged more than 15% (Table 3).

Psychometric properties: Reliability and validity

We obtained a value for Cronbach’s alpha of 0.69, very close to the minimum 0.7 acceptable value for analyzing internal consistency as a measure of reliability. Moreover, to assess the stability of the measure, the ICC for the EQ index and the EQ VAS was calculated, obtaining a value of 0.01 (95% confidence interval [CI] –0.32 to 0.26 p = 0.461), indicating a poor correlation.

The correlation between EQ index and EQ VAS was R = 0.371, p < 0.001). The correlation between the five dimensions of the EQ and the corresponding assessment scales (Tinetti, Barthel, Lawton, GDS, and VAS pain), categorized into three levels as indicated in the Methods, was analyzed to determine the convergent validity. Significant correlations were found in all dimensions: the strongest was for anxiety (>0.7), followed by usual activities (>0.6) and pain (>0.5) (Table 4).

Table 4

Convergent validity. Correlation between EuroQol 5 Dimensions and assessment scales (n = 188)

EuroQol 5 dimensions	Comprehensive geriatric assessment scales	r
1. Mobility	Tinetti Index	0.371^*
2. Self-care	Barthel Index	0.340^*
3. Usual activities	Lawton Index	0.628^*
4. Pain	VAS pain	0.504^*
5. Anxiety	Geriatric Depression Scale	0.703^*

VAS, visual analog scale; ^* p < 0.001.

To assess the divergent validity, we analyzed the correlations between continuous values of the EQ VAS and the geriatric assessment scales. As shown in Fig. 2, there were low, statistically significant correlations between the EQ VAS, but the Tinetti and Barthel Indexes were more than 0.3.

Fig. 2

Scatter plot between the EQ VAS and the Geriatric Assessment scales. A) Tinetti Index (0–28: lower scores = more dependence in mobility). B) Barthel Index (0–100: lower scores = more dependence in activities of daily living). C) Lawton Index (0–8: lower scores = more dependence in instrumental activities of daily living). D) The Geriatric Depression Scale GDS (0–10: higher scores = more depression). E) The visual analog scale VAS (1–10: higher scores = more pain). *p < 0.001.

Finally, using the EQ index and the EQ VAS as outcome variables, we performed two linear regressions. We included the scores of the scales categorized in three levels and adjusted for age and sex, as explanatory variables. For both the EQ index and the EQ VAS, the model showed a statistically significant relationship, with greater association and R² for EQ index than for EQ VAS (EQ index: F = 26.57; p < 0.001; R = 0.691; R² = 0.477; EQ VAS: F = 11.44; p < 0.001; R = 0.555; R² = 0.311). The Barthel Index (ADL) was the variable that was most strongly (and negatively) correlated with EQ index, whereas the Tinetti Index (gait and balance) was most strongly (and negatively) correlated with EQ VAS (Table 5).

Table 5

Multivariate linear regression analysis with EQ-5D Index and VAS as dependent variables (n = 188)

	EQ index β (95% CI)	P	EQ VAS β (95% CI)	P
Constant	0.83 (0.78, 0.88)	<0.001	82.87 (76.91,88.82)	<0.001
Barthel	–0.16 (–0.26, –0.05)	0.005	–4.4 (–17.13, 8.32)	0.495
Lawton	–0.06 (–0.15, –0.04)	0.002	–5.54 (–6.30,7.55)	0.859
Tinetti	–0.07 (–0.13, –0.01)	0.024	–13.14 (–20.39, –5.89)	<0.001
VAS	–0.12 (–0.16, –0.07)	<0.001	–10.44 (–15.74, –5.14)	<0.001
GDS	–0.13 (–0.018, –0.08)	<0.001	–11.60 (–17.64, –5.57)	<0.001

CI, confidence interval; GDS, Geriatric Depression Scale; VAS, visual analog scale.

DISCUSSION

In recent years there has been an increase in the measurement of HRQoL in people with cognitive impairment. There are many specific tools, but despite the current lack of standardization on the best measurement instrument, few studies have analyzed the validity of the generic HRQoL measurement tools [17, 18] in order to be able to compare results with other studies. The present study aimed to analyze the measurement properties of the generic EQ-5D scale in community-dwelling older adults with cognitive impairment. The generic scale has adequate feasibility, acceptability and reliability. The validity of EQ index was stronger than the EQ VAS.

The sample presented a good quality of life, as reflected by the high percentage of participants without problems in the dimensions and in the ceiling effect of the EQ index and EQ VAS although it is lower than other studies on community-dwelling older people with dementia [41]. Older people with cognitive impairment have higher HRQoL when they live in the community compared to an institution. Social factors, dependence, and comorbidity affect this population negatively [42].

Feasibility measurement properties of EQ-5D can be considered acceptable. Despite arguments from some authors indicating the need for the use of a proxy or caregiver intervention in QoL analysis [19], we obtained a good response from the older adults, with few missing data and all data computable. This may be due to the ease of use of the scale as well as the stage of cognitive impairment selected in the inclusion criteria.

Acceptability was good, but some aspects did not met criteria such as the ceiling effect and the divergence in the SD. This aspect is similar to several specific scales for elderly people with dementia, where results on these points have also been poor [18]. This may be due to the characteristics of this pathology, which impede the correct collection of data in some stages.

Internal consistency was limited in the analyzed sample, as evaluated in the reliability analysis by means of the Cronbach's alpha, which showed a moderate value close to 0.7 and a poor ICC between the EQ index and EQ VAS. This value is lower than most of the specific scales that analyze HRQoL in older people with cognitive impairment [18], although better values than in other studies using the same scale and proxies for the assessment [16, 23]. This feature could be responsible for a decrease in the values obtained in the generic scale.

On the other hand, good values were observed for construct validity. There was a moderate correlation between the EQ index and the EQ VAS. This may be due to the fact that the EQ index is the result of the effect of the dimensions that are more stable from one day to the next, while the EQ VAS [22] is more sensitive to change, since it responds to how people are feeling at the time of the evaluation. While this aspect may result in lower validity values for the EQ VAS in older people with cognitive impairment [16, 21], some authors argue that it is a valid measure for evaluating interventions [43].

Currently there is no tool considered to be the gold standard for assessing HRQoL, and this makes it difficult to test the validity of the different instruments available [23, 24]. Comparing the dimensions of the EQ-5D and the geriatric assessment scales corresponding to each dimension helps us to understand the validity based on scales widely used in the geriatric field. In addition, we observed greater validity in community-dwelling compared to institutionalized older people [21].

The divergent validity of the EQ VAS and the rating scales was adequate, indicating that the EQ VAS is an easily obtainable complementary measure. The correlation found with respect to independence in mobility and self-care indicate that these dimensions are essential in the perception of quality of life in older adults [44]. Finally, a high R² is observed in both regressions (but higher in the EQ index), suggesting that rating scales could be a good tool to analyze the validity of the EQ-5D in this population.

Knowing the measurement properties of the EQ-5D in the community-dwelling older adults with cognitive impairment could encourage clinicians and decision-makers to use a generic scale that is already used in community-dwelling older adults, enabling the comparison of interventions in different populations [45]. The measurement properties are acceptable, and although they are lower than the specific tools in some aspects [17, 18], professionals should bear in mind that long and difficult-to-use scales could limit the achievement of results in this population [46].

There are many studies on the use of different specific tools for assessing HRQoL in institutionalized older people [18], but there is less evidence for those dwelling in the community. It is necessary to carry out multicenter studies with different populations in addition to intensifying the study according to stages of severity of dementia.

The present study has some limitations. First of all, results may be different if groups are analyzed according to MMSE ranges (moderate or severe) and participants’ level of education has not been analyzed either. Several measurement properties were not analyzed, such as interobserver validity, as this was a self-administered questionnaire. Likewise, our research team opted not to do a test-retest in order not to make older people return to the health care center another day, even though the EQ VAS assesses the perceived health state in the moment that the scale is used, and this could vary if completed on different days. We also did not analyze different formats of the form, for example, a digital tool. Moreover, we did not consider participants’ comorbidities, frailty, sarcopenia, or cohabitation at home, which could interfere with the results.

Conclusions

We obtained acceptable values on measurement properties of the EQ-5D in community-dwelling older adults with cognitive impairment. This generic scale could be used for assessing HRQoL in this older population in order to compare results in a non-pathological population. It is necessary to analyze the dimensions and the EQ index since yield better measurement properties with respect to the EQ VAS.

Footnotes

ACKNOWLEDGMENTS

The authors would like to thank all of the participants in this research, without whom the study would not have been possible, and the Universidad Católica de Valencia “San Vicente Mártir” for its support.

This research received no external funding. Translation and publication costs were covered by the Universidad Católica San Vicente Mártir

Authors’ disclosures available online ().

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