Background
The EQ-5D is one of the most commonly used generic measures of health-related quality of life in the world. It assesses five dimensions of health including mobility, self-care, usual activities, pain/discomfort, and anxiety/depression, along with a visual analogue scale (EQ VAS) that assesses overall health. The EQ-5D is widely used for its applicability to most patient groups and ease of use when a simple, general measure of health is needed [1]. It is available in over 150 languages, with over 75 national value sets, and population norms for over 20 countries [2]. The EQ-5D is applied in a variety of research and clinical practice settings, including clinical trials, cost-utility analysis, population health assessment, and as a patient-reported outcome measure (PROM) for routine outcome measurement within health systems [3‐5].
Population reference data or population norms (also referred to as normative data) have been widely used to aid the interpretation of measures like the EQ-5D. They provide baseline or reference values that can be used to benchmark patients’ outcomes, evaluate clinical programs, as well as to establish burden of illness in the general population, and to assess health inequalities [6‐12]. National population norms are increasingly available for the five level version of the EQ-5D (EQ-5D-5L) in many countries including United States [13], France [14], Germany [15], Norway [16], Denmark [17], Italy [18], Portugal [19], Bulgaria [20], Romania [21], Slovenia [22], Russia [23], Australia [24, 25], New Zealand [26], India [27], Thailand [28], Vietnam [29], Japan [30], China [31], Colombia [32], Uruguay [33], Belize [34], and Trinidad and Tobago [35]. In Canada, population norms for the EQ-5D-5L are available at a national level [36], and for the province of Quebec only [37].
Alberta, a province in western Canada with a population of approximately 4.76 million people, relies on its provincial healthcare system to serve its residents. Since 2015, Alberta’s health authorities have adopted the EQ-5D-5L as the standard generic PROM for use in routine outcome measurement across the healthcare system [38, 39]. Given the prominent role of the EQ-5D-5L in Alberta’s healthcare evaluations, there is a pressing need to develop population norms specific to the province. These norms are crucial for accurately interpreting scores for different patient groups and ensuring relevant benchmarking, such as in provincial rehabilitation programs [40]. This need has been highlighted by key stakeholders and end-users of PROMs in Alberta [41]. Considering the diversity among Canada’s 13 provinces and territories and the notable differences in their healthcare systems, having localized EQ-5D-5L norms is essential for meaningful application and interpretation of the instrument within Alberta.
The objective of this study was to estimate normative values for the EQ-5D-5L dimensions, EQ-5D-5L index score, and visual analogue scale (EQ VAS) scores for the general adult population in Alberta, Canada. The norms are presented for the overall population, and across age, sex, five health zones, and for common chronic conditions. We also compared the EQ-5D-5L norms for Alberta with those reported for Quebec and with the national Canadian norms, as well as with those reported for other countries representing various regions in the world.
Methods
Data sources
Data from the Alberta Health “Alberta Community Health survey” (ACHS) for the years 2014, 2015, 2016, 2017, 2018, 2019, 2020 and 2021 [42], and data from the Health Quality Council of Alberta (HQCA) “Satisfaction and Experience with Healthcare Services” survey for the years 2012, 2014, 2016 [43] were used. This comprehensive dataset, spanning nearly a decade, ensures robust coverage and representativeness of Alberta’s general population—critical factors for accurate population norms estimation. Many existing studies rely on data from selective samples or non-representative surveys, as noted by Szende et al. in their seminal book on EQ-5D-3L population norms [44]. By leveraging this extensive and representative data, our approach aims to provide more reliable and applicable norms for Alberta.
ACHS and HQCA surveys are repeated cross-sectional, population-based, and use similar quota-based sampling approaches. These independent surveys included residents of Alberta, aged 18 years and older who were living in a household at the time of the survey’s administration. Eligible participants completed the survey over the phone via Computer-Assisted Telephone Interview (CATI) technology. Telephone numbers were dialed at least five times or until a final disposition. Potential respondents were called on various days and at different times of the day to increase the likelihood of securing an interview. Sampling frames of telephone numbers were based on landlines and cell phones and excluded businesses and government exchanges. Sampling quotas for these surveys were based on healthcare registration data from the previous year and designed to ensure that the final samples were representative of age, gender, and composition of the five Alberta Health Zones.
In addition to the EQ-5D-5L, participants answered questions on socio-demographics including age, sex, postal code, education, and income. In some cycles of these surveys, an additional question on whether an individual was diagnosed with any of the following health conditions was asked: chronic obstructive pulmonary disease (COPD), diabetes, cancer, history of cancer, depression, anxiety, asthma, hypertension, hyperlipidemia, sleep apnea, congestive heart failure, obesity, chronic pain, arthritis, heart disease, stroke, kidney disease, and bowel disease. Subsequently, data from a subset of surveys were used for estimating EQ-5D-5L norms for these chronic conditions.
The EQ-5D-5L
The EQ-5D-5L descriptive system assesses five dimensions of health (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), each with five levels of problems ranging from no problem (level 1) to extreme problem/unable to (level 5), together describing 3125 distinct health states. This version of the EQ-5D is considered to have better measurement properties than its predecessor the EQ-5D-3L (containing three levels of problems per dimension) [45, 46]. The EQ VAS is anchored at 0 for “the worst health you can imagine” and 100 for “the best health you can imagine”. In this study, index scores were calculated using the Canadian EQ-5D-5L value set [47], with scores ranging from − 0.149 (for the worst health state 55555) to 0.949 (for the best health state 11111). Typically, three different parameters are reported from the EQ-5D-5L measure: (1) the proportion of reported problems in each level for each dimension, (2) the index score, and (3) the EQ VAS score. The recommended minimal important difference of 0.04 [48] was used for interpreting differences in the EQ-5D-5L index score in this study.
Statistical analysis
Although the 11 datasets that we sourced for this analysis were derived using similar methodologies, we further evaluated the feasibility and appropriateness of merging them by comparing samples’ socio-demographic and EQ-5D-5L data across the surveys, with a particular focus on the years during which the COVID pandemic took place (2020–2021). Results suggested that the samples were very similar across all datasets, and EQ-5D-5L data was similar across the survey years, with negligible variations (Supplementary Table 1). Additionally, the percentage of missing EQ-5D-5L data was minimal in all datasets ranging from 0.4 to 1.9%, with an average of 1.4% across all datasets. As such, data from the 11 datasets were merged and complete EQ-5D-5L data were used for the generation of population norms.
In each survey wave, each sample person was assigned a numerical sample weight that measured the number of people in the population represented by that specific person. The survey weights account for the sampling design and have post stratification adjustments for month, age, sex, health zone, and telephone types (cell vs. landline). In the pooled sample, we created a new weight variable by dividing the original weights by the number of years (11 years) of data pooled so that it represents the average annual population size of the pooled time period using the method described by Thomas and colleagues [49]. We examined the sample representativeness before and after weighting. Demographic data for Alberta from the 2016 Canadian Census was used as reference data for this comparison [50].
We explored weighted EQ-5D-5L dimensions in the whole population and then in terms of age group (18–24, 25–34, 35–44, 45–54, 55–64, 65–74, ≥ 75 years), sex (male, female), health zones (urban zones: Calgary, Edmonton; rural zones: South, North; sub-urban zone: Central) and 17 chronic conditions. Further, we estimated weighted EQ-5D-5L index and EQ VAS scores. In further analysis, level 1 on each dimension of the EQ-5D-5L was labeled as “no problems” and levels 2–5 were combined into “present problems”. Finally, we compared EQ-5D-5L population norms in Alberta to those reported in 16 other jurisdictions and countries, including the province of Quebec and national Canadian norms. To assess differences in the proportion of reported problems across EQ-5D-5L dimensions across sub-groups, we employed the chi-square test. For comparing differences in EQ-5D-5L index scores and EQ VAS scores across subgroups and between Alberta and other jurisdictions/countries, we used Welch’s t-test and one-way ANOVA as appropriate.
Descriptive analysis included reporting of means, standard deviation [SD], 95% confidence interval, median (and interquartile range [IQR]) for continuous variables. Proportions (%) were reported for categorical variables. All analyses were conducted using STATA version 17.
Results
Study population
The total sample from the 11 datasets was 61,324, out of which 60,447 (98.6%) individuals had complete EQ-5D-5L data and were included in this analysis. Applying survey weights led to better representative samples compared to the Alberta general population in terms of age, sex, and distribution across the five health zones (Supplementary Table 2). As such, weighted data was used throughout the study and results were reported based on weighted estimates.
EQ-5D-5L norms in the overall population
The proportion of reported problems in EQ-5D-5L dimensions was highest for pain/discomfort (62.2%) and anxiety/depression (41.7%), followed by usual activities (24.2%), mobility (23.9%), and 5.5% in self-care (Table 1). The mean EQ-5D-5L index score in the overall population was 0.845 (SD 0.137) and that of the EQ VAS score was 77.4 (SD 16.7) (Table 3), with a highly skewed distribution (Figs. 1 and 2). Notably, 22.5% of the sample (N = 13,583) did not report any problems across all dimensions, thus reporting a health state of 11,111. Conversely, only one individual reported level 5 problems in all dimensions. The percentage of ceiling effect decreased with age, and was similar in males and females and across the five health zones (Table 3). Approximately 32.5% of the sample exhibited one of four health states with mild or moderate problems in pain/discomfort or anxiety/depression dimensions (11121, 11112, 11131, 11122) (Supplementary Table 3).
Table 1
Distribution of responses to EQ-5D-5L dimensions by age and sex
EQ-5D-5L Dimension | Age Group | Sex | All | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
18–24 | 25–34 | 35–44 | 45–54 | 55–64 | 65–74 | 75+ | Male | Female | |||
Mobility | Level 1 | 91.0% | 89.4% | 85.2% | 75.6% | 67.8% | 58.5% | 45.0% | 77.8% | 75.0% | 76.1% |
Level 2 | 6.7% | 7.2% | 9.5% | 14.7% | 18.1% | 21.3% | 25.1% | 13.2% | 13.9% | 13.6% | |
Level 3 | 1.5% | 2.8% | 3.9% | 6.6% | 9.6% | 14.1% | 20.7% | 6.1% | 8.0% | 7.2% | |
Level 4 | 0.8% | 0.4% | 1.1% | 2.8% | 3.9% | 5.4% | 8.0% | 2.5% | 2.9% | 2.7% | |
Level 5 | 0.1% | 0.3% | 0.3% | 0.3% | 0.6% | 0.7% | 1.2% | 0.5% | 0.4% | 0.4% | |
p-value | < 0.001 | < 0.001 | |||||||||
Self-care | Level 1 | 97.0% | 96.9% | 96.7% | 94.0% | 92.3% | 92.0% | 88.8% | 94.8% | 94.2% | 94.5% |
Level 2 | 2.5% | 2.1% | 2.3% | 3.4% | 5.0% | 4.9% | 7.2% | 3.3% | 3.7% | 3.6% | |
Level 3 | 0.4% | 0.9% | 0.9% | 2.2% | 2.4% | 2.8% | 3.3% | 1.7% | 1.7% | 1.7% | |
Level 4 | 0.1% | 0.1% | 0.1% | 0.3% | 0.2% | 0.3% | 0.4% | 0.2% | 0.2% | 0.2% | |
Level 5 | 0.1% | 0.1% | 0.1% | 0.1% | 0.2% | 0.1% | 0.2% | 0.1% | 0.1% | 0.1% | |
p-value | < 0.001 | 0.176 | |||||||||
Usual Activities | Level 1 | 83.1% | 84.7% | 83.2% | 75.5% | 70.4% | 64.4% | 54.6% | 78.4% | 73.7% | 75.8% |
Level 2 | 13.3% | 10.1% | 11.1% | 14.2% | 17.5% | 21.5% | 24.2% | 13.4% | 16.1% | 14.9% | |
Level 3 | 3.1% | 4.1% | 4.3% | 7.1% | 8.9% | 11.2% | 17.7% | 6.2% | 7.8% | 7.1% | |
Level 4 | 0.4% | 0.7% | 0.9% | 2.1% | 2.3% | 2.0% | 2.2% | 1.4% | 1.6% | 1.5% | |
Level 5 | 0.1% | 0.4% | 0.6% | 1.1% | 1.1% | 0.9% | 1.3% | 0.7% | 0.9% | 0.8% | |
p-value | < 0.001 | < 0.001 | |||||||||
Pain/ Discomfort | Level 1 | 55.2% | 49.9% | 42.6% | 34.0% | 27.6% | 24.1% | 23.2% | 40.5% | 35.3% | 37.6% |
Level 2 | 34.3% | 35.5% | 40.5% | 41.1% | 42.6% | 42.8% | 38.3% | 39.5% | 39.7% | 39.7% | |
Level 3 | 9.0% | 12.1% | 12.9% | 18.3% | 23.0% | 25.8% | 30.6% | 15.8% | 19.2% | 17.7% | |
Level 4 | 1.1% | 1.8% | 2.9% | 5.0% | 5.6% | 6.2% | 7.0% | 3.2% | 4.7% | 4.0% | |
Level 5 | 0.4% | 0.7% | 1.0% | 1.6% | 1.2% | 1.0% | 0.9% | 0.9% | 1.1% | 1.0% | |
p-value | < 0.001 | < 0.001 | |||||||||
Anxiety/ Depression | Level 1 | 47.6% | 51.7% | 57.3% | 57.5% | 62.2% | 66.4% | 68.8% | 62.5% | 54.2% | 58.0% |
Level 2 | 28.7% | 28.1% | 26.5% | 26.9% | 24.4% | 22.2% | 22.0% | 24.2% | 27.3% | 25.9% | |
Level 3 | 17.9% | 15.1% | 13.2% | 12.1% | 10.9% | 10.1% | 8.7% | 10.8% | 14.5% | 12.8% | |
Level 4 | 3.7% | 4.1% | 2.2% | 2.7% | 1.8% | 1.0% | 0.4% | 1.9% | 3.0% | 2.4% | |
Level 5 | 2.0% | 1.1% | 0.8% | 0.9% | 0.7% | 0.3% | 0.1% | 0.7% | 1.1% | 0.9% | |
p-value | < 0.001 | < 0.001 | |||||||||
Table 2
Distribution of responses to EQ-5D-5L dimensions by AHS zone
EQ-5D-5L dimension AHS zone | |||||||
|---|---|---|---|---|---|---|---|
South | Calgary | Central | Edmonton | North | All | ||
Mobility | Level 1 | 71.0% | 78.8% | 73.1% | 75.7% | 76.0% | 76.2% |
Level 2 | 15.1% | 12.1% | 15.6% | 13.9% | 13.8% | 13.5% | |
Level 3 | 10.1% | 6.4% | 7.8% | 7.0% | 7.4% | 7.2% | |
Level 4 | 3.3% | 2.4% | 2.9% | 2.9% | 2.5% | 2.7% | |
Level 5 | 0.6% | 0.3% | 0.6% | 0.5% | 0.3% | 0.4% | |
p-value | < 0.001 | ||||||
Self-care | Level 1 | 92.4% | 95.2% | 94.3% | 94.1% | 94.5% | 94.5% |
Level 2 | 4.7% | 3.2% | 3.6% | 3.8% | 3.6% | 3.6% | |
Level 3 | 2.5% | 1.4% | 1.8% | 1.8% | 1.7% | 1.7% | |
Level 4 | 0.2% | 0.2% | 0.2% | 0.2% | 0.2% | 0.2% | |
Level 5 | 0.1% | 0.1% | 0.2% | 0.1% | 0.1% | 0.1% | |
p-value | < 0.001 | ||||||
Usual activities | Level 1 | 71.2% | 78.3% | 71.8% | 75.8% | 75.7% | 75.9% |
Level 2 | 16.4% | 13.5% | 18.0% | 14.7% | 15.0% | 14.8% | |
Level 3 | 9.1% | 6.3% | 7.6% | 7.3% | 7.3% | 7.1% | |
Level 4 | 2.4% | 1.2% | 1.7% | 1.6% | 1.2% | 1.5% | |
Level 5 | 1.1% | 0.7% | 0.9% | 0.8% | 0.8% | 0.8% | |
p-value | < 0.001 | ||||||
Pain/ discomfort | Level 1 | 33.2% | 40.4% | 33.6% | 38.3% | 34.9% | 37.8% |
Level 2 | 40.1% | 39.1% | 40.8% | 39.2% | 40.2% | 39.5% | |
Level 3 | 20.5% | 16.1% | 19.7% | 17.3% | 19.9% | 17.7% | |
Level 4 | 5.0% | 3.5% | 4.8% | 4.1% | 4.0% | 4.0% | |
Level 5 | 1.2% | 0.9% | 1.0% | 1.2% | 1.0% | 1.0% | |
p-value | < 0.001 | ||||||
Anxiety/ depression | Level 1 | 57.0% | 59.2% | 59.8% | 56.2% | 60.8% | 58.3% |
Level 2 | 26.0% | 25.8% | 24.8% | 26.6% | 23.3% | 25.7% | |
Level 3 | 12.1% | 12.1% | 12.8% | 13.5% | 12.8% | 12.7% | |
Level 4 | 3.5% | 2.3% | 1.8% | 2.7% | 2.2% | 2.4% | |
Level 5 | 1.5% | 0.6% | 0.9% | 1.0% | 1.0% | 0.9% | |
p-value | < 0.001 | ||||||
Fig. 1
Distribution of EQ-5D-5L index scores (N = 60,447)
×
![]()
Fig. 2
Distribution of EQ-5D-5L VAS scores (N = 60,206)
×
![]()
EQ-5D-5L norms by age
The proportion of reported problems in EQ-5D-5L dimensions increased with age, with a notable exception in the anxiety/depression dimension, where older respondents reported fewer problems than their younger counterparts (Table 1; Supplementary Fig. 1). The mean index score declined with age from 0.871 (SD 0.102) in those aged 18–24 years to 0.800 (SD 0.148) in 75-year-old or older individuals (Table 3). Similarly, the mean EQ VAS score demonstrated a decreasing trend with age, ranging from 80.2 (SD 14.1) in the 18–24 age group to 74.1 (SD 18.9) in those aged 75 years or more. Differences in reported problems in all dimensions across age groups were statistically significant.
EQ-5D-5L norms by sex
Overall, females consistently reported more problems in all EQ-5D-5L dimensions compared to males, all differences were statistically significant except in self-care (Table 1, Supplementary Fig. 2). The largest differences were observed in the pain/discomfort and anxiety/depression dimensions. Whereas 59.5% of males reported mild-severe pain/discomfort compared to 64.7% of females. Similarly, 37.5% of males reported mild-severe anxiety/depression compared to 45.8% of females. Smaller yet consistent variations were observed in the mobility (22.2% in males vs. 25% in females), usual activities (21.6% in males vs. 26.3% in females), and self-care (5.2% in males vs. 5.8% in females) dimensions.
Similar results were observed when the distribution of responses to EQ-5D-5L dimensions was examined by sex across the seven age groups, whereby females in all age groups reported more problems in all dimensions compared to males (Supplementary Tables 4 and 5). The mean EQ-5D-5L index score was consistently lower in females compared to males in all age groups, with differences ranging from 0.02 in the youngest age group to 0.024 in those aged 75 years or older (Supplementary Table 6; Supplementary Fig. 4). Meanwhile, the pattern of EQ VAS scores across different age groups exhibited variations in males compared to females, albeit with differences of smaller magnitude (Supplementary Table 6; Supplementary Fig. 5).
EQ-5D-5L norms by health zone
Despite being statistically significant, variations in the proportion of reported problems in EQ-5D-5L dimensions across the five Alberta health zones were marginal (Table 2, Supplementary Fig. 3). Notably, respondents in the South zone, which is considered a mostly rural area with some small cities, reported slightly more problems than those in other zones, and had slightly lower index and VAS scores. Conversely, respondents in the Calgary zone, which is considered a metropolitan area, had the least reported problems and the highest mean index and VAS scores.
EQ-5D-5L norms by chronic conditions
Respondents who reported having chronic pain had the lowest mean index score (0.697, SD 0.202), while those with congestive heart failure reported the lowest mean VAS score (59.0, SD 21.0) compared to other conditions (Table 4). Mild to severe problems in mobility were predominantly reported by respondents with congestive heart failure (68.6%), followed by those with COPD (64.4%) and stroke (63.0%) (Table 5). Respondents with mild to severe problems in self-care were mostly those with stroke (26.4%), followed by those with COPD (18.3%) and chronic pain (18.2%). In usual activities, respondents with congestive heart failure reported the highest prevalence of mild to severe problems (63.9%), followed by those with chronic pain (61.1%) and stroke (59.4%). Mild to severe levels of pain/discomfort were predominantly reported by respondents with chronic pain (97.1%), followed by arthritis (88.6%) and kidney disease (88.6%). Lastly, individuals reporting mild to severe symptoms of anxiety/depression were with scores mostly those with anxiety (92.6%), followed by depression (91.7%) and COPD (53.5%).
Table 3
EQ-5D-5L index and VAS scores in the overall sample and by age group, sex, and AHS zone
Index score | VAS score | % ceiling | |||||||
|---|---|---|---|---|---|---|---|---|---|
Mean (SD) | 95% CI | Median (IQR) | P-value | Mean (SD) | 95% CI | Median (IQR) | P-value | ||
Overall | 0.845 (0.137) | (0.841, 0.848) | 0.885 (0.949 − 0.823) | 77.4 (16.7) | (77.0, 77.9) | 80 (70–90) | 22.5% | ||
Age group | |||||||||
18–24 | 0.871 (0.102) | (0.863, 0.879) | 0.905 (0.854–0.949) | < 0.001 | 80.2 (14.1) | (79.1, 81.4) | 84 (75–90) | < 0.001 | 30.3% |
25–34 | 0.867 (0.114) | (0.859, 0.874) | 0.905 (0.847–0.949) | 78.9 (15.2) | (77.9, 79.9) | 80 (75–90) | 31.3% | ||
35–44 | 0.863 (0.122) | (0.856, 0.871) | 0.905 (0.847–0.949) | 78.5 (15.6) | (77.5, 79.4) | 80 (73–90) | 28.7% | ||
45–54 | 0.837 (0.152) | (0.827, 0.847) | 0.874 (0.821–0.911) | 75.9 (17.7) | (74.8, 77.1) | 80 (70–90) | 23.3% | ||
55–64 | 0.827 (0.153) | (0.818, 0.837) | 0.867 (0.802–0.905) | 76.1 (17.8) | (75.0, 77.3) | 80 (70–90) | 18.5% | ||
65–74 | 0.820 (0.148) | (0.808, 0.831) | 0.866 (0.784–0.905) | 76.5 (17.7) | (75.1, 77.9) | 80 (70–90) | 17.9% | ||
75+ | 0.800 (0.148) | (0.784, 0.817) | 0.846 (0.750–0.905) | 74.1 (18.9) | (72.0, 76.2) | 80 (70–85) | 14.0% | ||
Sex | |||||||||
Male | 0.854 (0.130) | (0.849, 0.859) | 0.905 (0.829–0.949) | < 0.001 | 77.5 (16.2) | (76.9, 78.1) | 80 (70–90) | 0.577 | 24.5% |
Female | 0.837 (0.143) | (0.831, 0.842) | 0.872 (0.810–0.911) | 77.4 (17.1) | (76.8, 78.0) | 80 (70–90) | 21.0% | ||
AHS zone | |||||||||
South | 0.827 (0.156) | (0.812, 0.842) | 0.867 (0.802–0.911) | < 0.001 | 76.4 (18.2) | (74.6, 78.2) | 80 (70–90) | < 0.001 | 21.2% |
Calgary | 0.854 (0.131) | (0.848, 0.859) | 0.905 (0.829–0.949) | 78.4 (16.0) | (77.7, 79.1) | 80 (74–90) | 24.7% | ||
Central | 0.839 (0.140) | (0.828, 0.849) | 0.874 (0.809–0.911) | 76.6 (17.3) | (75.2, 77.9) | 80 (70–90) | 21.1% | ||
Edmonton | 0.842 (0.139) | (0.835, 0.849) | 0.874 (0.821–0.929) | 77.1 (16.8) | (76.3, 77.9) | 80 (70–90) | 23.0% | ||
North | 0.845 (0.135) | (0.834, 0.856) | 0.885 (0.823–0.911) | 76.7 (17.2) | (75.3, 78.1) | 80 (70–90) | 20.9% | ||
Table 4
EQ-5D-5L index and VAS scores in different chronic conditions
Index score | VAS score | |||||
|---|---|---|---|---|---|---|
Chronic Condition | Mean (SD) | 95% CI | Median (IQR) | Mean (SD) | 95% CI | Median (IQR) |
COPD (n = 1680)* | 0.720 (0.206) | (0.683, 0.757) | 0.784 (0.627–0.867) | 62.8 (21.8) | (58.9, 66.7) | 70 (50–80) |
Diabetes (n = 3327)* | 0.781 (0.184) | (0.758, 0.803) | 0.846 (0.743–0.905) | 68.6 (19.6) | (66.2, 71.0) | 75 (60–80) |
History of cancer (n = 2371)€ | 0.809 (0.154) | (0.786, 0.832) | 0.866 (0.764–0.905) | 75.3 (17.7) | (72.6, 77.9) | 80 (70–90) |
Depression (n = 3515)€ | 0.710 (0.198) | (0.688, 0.732) | 0.785 (0.615–0.854) | 64.8 (20.6) | (62.5, 67.1) | 70 (50–80) |
Anxiety (n = 2735) € | 0.707 (0.199) | (0.683, 0.732) | 0.784 (0.600–0.860) | 65.4 (20.9) | (62.8, 68.0) | 70 (50–80) |
Asthma (n = 921)a | 0.801 (0.178) | (0.762, 0.839) | 0.867 (0.764–0.910) | 72.6 (18.2) | (68.8, 74.1) | 75 (64–85) |
Hypertension (n = 2167)a | 0.806 (0.160) | (0.782, 0.830) | 0.860 (0.764–0.905) | 71.4 (17.5) | (68.8, 74.1) | 75 (60–85) |
Hyperlipidemia (n = 1440)a | 0.810 (0.161) | (0.780, 0.839) | 0.866 (0.782–0.905) | 72.0 (16.8) | (68.9, 75.0) | 75 (60–85) |
Sleep apnea (n = 781)a | 0.755 (0.199) | (0.706, 0.803) | 0.823 (0.706–0.905) | 66.5 (19.3) | (61.8, 71.2) | 70 (60–80) |
Congestive heart failure (n = 134)a | 0.728 (0.206) | (0.594, 0.861) | 0.785 (0.668–0.867) | 59.0 (21.0) | (45.2, 72.9) | 60 (50–75) |
Obesity (n = 1098)a | 0.778 (0.176) | (0.741, 0.814) | 0.829 (0.743–0.905) | 67.8 (16.9) | (64.3, 71.3) | 70 (60–80) |
Chronic pain (n = 1944)a | 0.697 (0.202) | (0.665, 0.728) | 0.771 (0.590–0.846) | 64.9 (19.5) | (61.9, 68.0) | 70 (50–80) |
Arthritis (n = 2563)a | 0.767 (0.179) | (0.742, 0.792) | 0.823 (0.725–0.885) | 70.7 (18.1) | (68.2, 73.2) | 75 (60–83) |
Heart disease (n = 553)a | 0.780 (0.181) | (0.727, 0.832) | 0.841 (0.727–0.905) | 67.7 (18.6) | (62.2, 73.1) | 70 (60–80) |
History of stroke (n = 121)a | 0.713 (0.222) | (0.564, 0.861) | 0.786 (0.622–0.867) | 63.6 (18.5) | (50.8, 76.3) | 70 (50–75) |
Kidney disease (n = 194)a | 0.718 (0.214) | (0.610, 0.825) | 0.802 (0.615–0.867) | 62.5 (22.0) | (51.3, 73.7) | 65 (50–80) |
Bowel disease (n = 535)a | 0.724 (0.218) | (0.660, 0.789) | 0.803 (0.616–0.885) | 65.5 (20.4) | (59.3, 71.6) | 70 (50–80) |
Table 5
Distribution of responses to EQ-5D-5L dimensions in different chronic conditions
EQ-5D-5L dimension | COPD | Diabetes | Cancer | H/O Cancer | Depression | Anxiety | Asthma | Hypertension | Hyperlipidemia | Sleep apnea | Congestive heart failure | Obesity | Chronic pain | Arthritis | Heart disease | Stroke | Kidney disease | Bowel disease | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mobility | Level 1 | 35.6 | 51.2 | 53.4 | 57.4 | 58.7 | 60.5 | 67.6 | 57.2 | 57.9 | 51.8 | 31.4 | 50.2 | 39.8 | 45.2 | 49.4 | 37.0 | 41.2 | 54.1 |
Level 2 | 27.2 | 22.3 | 21.2 | 21.3 | 19.8 | 18.7 | 16.4 | 22.6 | 22.5 | 22.6 | 28.0 | 25.9 | 29.1 | 29.8 | 25.7 | 21.3 | 24.3 | 19.8 | |
Level 3 | 22.0 | 17.5 | 16.7 | 14.9 | 14.0 | 13.3 | 11.3 | 14.1 | 14.0 | 15.7 | 25.9 | 16.8 | 20.3 | 17.1 | 14.9 | 23.6 | 21.4 | 17.8 | |
Level 4 | 13.6 | 7.7 | 7.8 | 6.0 | 7.0 | 7.2 | 4.2 | 5.4 | 4.7 | 8.7 | 14.1 | 6.2 | 9.3 | 6.9 | 8.8 | 14.2 | 12.5 | 6.9 | |
Level 5 | 1.5 | 1.3 | 0.9 | 0.4 | 0.6 | 0.3 | 0.5 | 0.7 | 0.9 | 1.1 | 0.6 | 1.0 | 1.5 | 1.1 | 1.2 | 4.0 | 0.6 | 1.4 | |
Self-care | Level 1 | 81.7 | 86.7 | 87.9 | 93.9 | 84.1 | 84.2 | 91.5 | 90.6 | 91.1 | 85.4 | 83.7 | 88.8 | 81.8 | 87.6 | 87.4 | 73.6 | 83.4 | 82.1 |
Level 2 | 10.5 | 7.9 | 7.8 | 6.3 | 9.9 | 9.8 | 5.9 | 5.8 | 5.4 | 8.2 | 11.2 | 6.6 | 11.2 | 8.0 | 7.5 | 14.8 | 9.2 | 10.7 | |
Level 3 | 6.5 | 4.5 | 3.9 | 2.4 | 5.5 | 5.4 | 2.3 | 2.7 | 2.5 | 5.2 | 2.6 | 3.4 | 5.4 | 3.2 | 3.5 | 8.5 | 6.3 | 5.4 | |
Level 4 | 0.8 | 0.5 | 0.2 | 0.2 | 0.4 | 0.6 | 0.3 | 0.4 | 0.5 | 1.0 | 1.2 | 0.7 | 0.7 | 0.6 | 0.8 | 1.7 | 0.5 | 0.9 | |
Level 5 | 0.5 | 0.4 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | 0.5 | 0.5 | 0.3 | 1.3 | 0.7 | 0.9 | 0.6 | 0.8 | 1.4 | 0.6 | 0.9 | |
Usual activities | Level 1 | 43.2 | 55.8 | 52.4 | 61.8 | 48.2 | 50.1 | 65.2 | 61.9 | 62.0 | 53.3 | 36.1 | 55.1 | 38.9 | 53.8 | 54.9 | 40.6 | 41.4 | 47.4 |
Level 2 | 26.1 | 23.1 | 22.4 | 22.2 | 27.1 | 25.2 | 18.3 | 20.0 | 19.9 | 23.3 | 24.4 | 23.7 | 27.7 | 24.4 | 21.3 | 21.7 | 25.3 | 22.2 | |
Level 3 | 21.4 | 16.2 | 20.6 | 12.8 | 17.1 | 17.6 | 11.6 | 14.3 | 13.9 | 16.8 | 31.6 | 14.9 | 23.5 | 16.5 | 17.9 | 27.7 | 25.2 | 20.7 | |
Level 4 | 6.7 | 3.2 | 2.7 | 2.2 | 5.2 | 5.1 | 3.3 | 2.8 | 2.9 | 3.9 | 7.1 | 4.9 | 6.6 | 3.9 | 4.8 | 7.3 | 4.7 | 6.6 | |
Level 5 | 2.6 | 1.8 | 1.8 | 1.0 | 2.4 | 2.1 | 1.7 | 1.1 | 1.3 | 2.7 | 0.8 | 1.4 | 3.3 | 1.5 | 1.2 | 2.7 | 3.4 | 3.2 | |
Pain/ discomfort | Level 1 | 14.8 | 22.2 | 22.4 | 23.5 | 18.6 | 20.6 | 29.9 | 25.1 | 26.2 | 20.2 | 23.1 | 19.8 | 2.9 | 11.4 | 25.1 | 27.6 | 13.4 | 16.8 |
Level 2 | 32.0 | 37.0 | 37.1 | 41.4 | 36.3 | 34.4 | 36.4 | 40.2 | 39.1 | 34.9 | 26.7 | 41.1 | 26.5 | 40.8 | 34.4 | 26.1 | 31.8 | 32.3 | |
Level 3 | 36.3 | 29.0 | 29.7 | 26.3 | 31.0 | 30.9 | 22.7 | 25.8 | 26.6 | 29.9 | 33.2 | 29.3 | 46.5 | 34.2 | 28.3 | 29.6 | 33.5 | 31.2 | |
Level 4 | 13.3 | 9.0 | 9.0 | 7.4 | 11.1 | 10.9 | 8.6 | 7.1 | 6.7 | 10.3 | 8.7 | 8.1 | 18.3 | 10.7 | 8.4 | 10.9 | 16.0 | 13.0 | |
Level 5 | 3.6 | 2.9 | 1.9 | 1.5 | 3.0 | 3.2 | 2.5 | 1.8 | 1.4 | 4.8 | 8.4 | 1.7 | 5.9 | 2.9 | 3.8 | 5.8 | 5.4 | 6.8 | |
Anxiety/ depression | Level 1 | 46.5 | 61 | 58.9 | 61.4 | 8.3 | 7.4 | 55.6 | 63.7 | 64.3 | 50.0 | 52.6 | 51.6 | 48.6 | 61.3 | 61.2 | 48.3 | 58.3 | 48.4 |
Level 2 | 27.1 | 22 | 24.7 | 25.0 | 28.6 | 26.3 | 23.9 | 22.5 | 21.4 | 26.7 | 26.6 | 25.8 | 25.7 | 21.5 | 23.0 | 26.6 | 17.6 | 24.0 | |
Level 3 | 19.8 | 13 | 14.0 | 11.7 | 44.1 | 44.9 | 13.4 | 10.7 | 11.5 | 16.6 | 16.4 | 17.5 | 17.9 | 12.9 | 13.1 | 17.6 | 15.8 | 16.6 | |
Level 4 | 5.4 | 3 | 1.9 | 1.7 | 14.8 | 16.3 | 5.3 | 2.2 | 2.1 | 4.6 | 3.0 | 3.7 | 5.6 | 3.1 | 1.5 | 6.5 | 4.8 | 7.4 | |
Level 5 | 1.3 | 1 | 0.6 | 0.3 | 4.3 | 5.0 | 1.8 | 1.0 | 0.8 | 2.2 | 1.3 | 1.4 | 2.1 | 1.3 | 1.1 | 1.1 | 3.5 | 3.7 | |
Comparison of EQ-5D-5L norms in Alberta to Canadian and international norms
Respondents in Alberta reported fewer problems across all EQ-5D-5L dimensions compared to those in Quebec [37] and to the national norms, except for pain/discomfort and anxiety/ depression whereby the reported problems were higher than the Canadian average [36] (Fig. 3). All differences were statistically significant except for mobility and usual activities compared to the Canadian norms. The EQ-5D-5L index score of the Alberta general population (mean 0.845, SD 0.137) was higher than that of Quebec (mean 0.824, range 0.818–0.829; p-value < 0.001), yet lower than the Canadian average of 0.864 (SD 0.121; p-value < 0.001). Similarly, the EQ VAS score of the Alberta general population (mean 77.4, SD 16.7) was higher than that of Quebec (mean 75.9, range 75.2–76.6; p-value < 0.001), yet lower than the Canadian average of 82.3 (SD 14.2; p-value < 0.001).
Fig. 3
Distribution of levels 2–5 on EQ-5D-5L dimensions in Alberta, Quebec, and Canada
×
![]()
In a global context, the EQ-5D-5L index score within the general population of Alberta was comparatively lower than that of 13 out of the 14 countries assessed, whose scores range from 0.805 in Norway [16] to 0.957 in China [31] (Fig. 4). Differences in the index score between Alberta and other jurisdictions were statistically significant except for India and US. Similarly, the EQ VAS score in Alberta was found to be lower than that of 10 out of 14 countries examined, whose scores range from 71.6 in Germany [15] to 87.4 in Vietnam [29] (Fig. 5). Differences in the EQ VAS score between Alberta and other jurisdictions were statistically significant except for Bulgaria and Norway.
Fig. 4
Mean EQ-5D-5L index score in Alberta and other 16 countries and jurisdictions
×
![]()
Fig. 5
Mean EQ VAS score in Alberta and other 16 countries and jurisdictions
×
![]()
Discussion
This study provides EQ-5D-5L norms for the general adult population in Alberta, using data from a representative sample of 60,447 respondents collected between 2012 and 2021. Although the distribution of scores in the Alberta population are significantly different from national and international norms, the observed variations and trends in EQ-5D-5L dimensions and index and EQ VAS scores with respect to age and sex groups have been reported in other countries [13, 14, 16, 18, 19, 31, 32, 36]. EQ-5D-5L norms were consistent across different health zones in Alberta, and were below the Canadian average. Nonetheless, average differences in the index score between Alberta, Quebec, and the Canadian national norms were smaller than the minimal importance difference of the EQ-5D-5L index score of 0.04 [48].
The study revealed that pain/discomfort and anxiety/depression are predominant issues in the Alberta general population, substantially contributing to lower EQ-5D-5L index scores. Noteworthy is the finding that 62.2% of respondents reported mild to severe levels of pain/discomfort, surpassing the Canadian average of 53.1% and exceeding the proportions observed in 14 other countries. Similarly, 41.7% reported mild to severe symptoms of anxiety/depression, a percentage higher than the national figure of 37.9% and surpassing proportions in 12 other surveyed countries (Supplementary Figs. 6 and 7). These statistics underscore an important public health concern that warrants thorough examination and targeted interventions by health authorities in Alberta.
Previous literature has consistently highlighted the decline in health-related quality of life along individuals with chronic conditions [51‐54], which was also observed in this study. This study underscores a few particularly worrisome and noteworthy observations. Across the 18 examined conditions, the prevalence of mild to extreme levels of pain/discomfort ranged from 70.1% in asthma to 97.1% in those with chronic pain and was also very high in conditions not often associated with pain, such as sleep apnea (79.8%) and depression (81.4%). These high levels of pain/discomfort significantly contribute to lower health-related quality of life, a nuance often obscured when relying solely on summary scores. Similarly, the prevalence of mild to extreme symptoms of anxiety/depression ranged from 35.7% in those with hyperlipidemia to 92.6% in those with an anxiety disorder. These figures hold significant implications for clinicians, particularly highlighting the substantial role of pain and mental health problems in the well-being of patients across diverse conditions.
The development of EQ-5D-5L norms in Alberta holds substantial importance for both research and clinical applications. These norms provide a comprehensive understanding of the health-related quality of life within the Alberta population, offering a valuable benchmark for assessing individual and group well-being. Clinically, these norms enable healthcare professionals to evaluate patient-reported outcomes systematically, aiding in the identification of areas that may require targeted interventions or additional support. Examples of these applications using an unpublished version of these norms have been previously reported [40, 55]. Further, initiatives that integrates these norms into clinical dashboards is also underway in the Alberta healthcare system [40]. Finally, the establishment of local norms facilitates comparisons with national and international standards, contributing to a more nuanced interpretation of health-related quality of life.
While this study used a substantial population-based sample spanning an extensive timeframe, ensuring a high level of representativeness of the general Alberta population, it is not without limitations. Firstly, combining data from 11 datasets required a trade-off in the specificity of the collected data across surveys. For instance, data on important socio-demographic factors such as education and income were collected slightly differently over the years, and as such, combining or comparing data on these variables was not possible, thereby restricting further in-depth analysis. Secondly, data on chronic conditions was based on self-report, and only captured the predetermined list available in the surveys, potentially omitting some clinically relevant conditions. Thirdly, the data spanned the worst period of the COVID-19 pandemic, which might affect respondents and health status; however, we compared data across the survey waves including those during the pandemic, and the differences were negligible. Lastly, caution is warranted when comparing norms to other countries or jurisdictions due to significant variability in the methodologies employed in these studies. For example, samples size ranged from approximately 1000, the level required for EQ-5D-5L valuation studies which was used in many studies, to 15,000 in the French study [14]. As such, and with lack of guidelines on estimating population norms for the EQ-5D, observed differences may result from methodological variations rather than actual differences in health-related quality of life across populations.
Conclusion
This study provides general adult population norms for the EQ-5D-5L descriptive system, index score and EQ VAS score for the province of Alberta, Canada. These norms will serve as a benchmark for EQ-5D-5L data collected in clinical practice and studies, and in various applications of EQ-5D-5L within the field of health economics and outcomes research. The findings highlight the importance of examining dimension-level data and solely rely on summary scores of the EQ-5D.
MO: Mobility; SC: self-care; UA: usual activities; PD: pain/discomfort; AD: anxiety/depression.
* Indicates that differences in the proportion of reporting problems in a specific dimension between Alberta and Quebec or Canada is statistically significant at p-value < 0.05.
* Indicates that differences in the index score between Alberta and that country/jurisdiction is statistically significant at p-value < 0.05.
* Indicates that differences in the EQ VAS score between Alberta and that country/jurisdiction is statistically significant at p-value < 0.05.
Declarations
Conflict of interest
FAS, AO, and JAJ are all members of the EuroQol Group. Other authors do not have any conflicts of interest to disclose.
Ethics approval
This study involved secondary analysis of collected data in health surveys commissioned by health authorities, and as such, ethics review and approval were waived. Informed consent was obtained from all individual participants who participated in the surveys.
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
