Health improvement is a multidimensional process requiring attention to both health levels and equity. This study examined nationwide trends in both the levels and equality of health-related quality of life (HRQoL) of Chinese residents during the COVID-19 pandemic (2021–2023).
Methods
Data were extracted from the Psychology and Behavior Investigation of Chinese Residents (PBICR) survey: 9,963 participants in 2021, 28,280 in 2022, and 45,003 in 2023. HRQoL was assessed using the EQ-5D-5 L. Changes in the weighted average EQ-5D-5L utility index (UI) and visual analogue scale (VAS) scores were assessed. OLS regression models were used to verify the changes in UI and VAS scores over time, controlling variations in other variables. The Erreygers Index (EI) was calculated to measure inequality in UI and VAS scores. RIF-EI-OLS models were employed to decompose contributors to EI scores.
Results
There was a slight decline in HRQoL over the study period, with 2021 showing the highest weighted average UI score (0.9363 ± 0.1389), compared to 0.9332 (SD = 0.1524) in 2022 (β=-0.0081, P < 0.0001) and 0.9244 (SD = 0.1546) in 2023 (β=-0.0143, P < 0.0001). The EI value for UI in 2021 was 0.0703, showing a decreasing trend to 0.0635 in 2022 (β=-0.0105, P < 0.001), with no further significant change in 2023. Regional disparities in both UI and EI were evident. Higher socioeconomic status (e.g., income, education) was associated with higher UI and lower EI scores. Chronic conditions were associated with lower UI scores, while co-morbidity was associated with higher EI scores. Higher UI and lower EI scores were also associated with higher health literacy and a better family environment. The predictors of VAS were similar to those for UI. The EI value for VAS showed an increasing trend.
Conclusions
From 2021 to 2023, residents in mainland China experienced a slight decline in HRQoL, accompanied by a lowered UI inequality but higher VAS inequality in 2022 and 2023. These may reflect how life and health change under the specific context of the COVID-19 pandemic.
Health is the indispensable prerequisite for the overall well-being of people and the foundation of economic and social development. In 2015, all 193 member states of the United Nations (UN) unanimously adopted the “2030 Agenda for Sustainable Development”, which aims to achieve 17 Sustainable Development Goals (SDGs) [1]. Health has a central place in SDG three: Ensure healthy lives and promote well-being for all at all ages [2]. Almost all of the other 16 goals are either directly related to health or contribute to health indirectly, encouraging countries to commit to improvements and advancements in the field of health. In 2016, China proposed the “Healthy China 2030” blueprint, with the core objective of raising health levels and regarding public health as a prerequisite for all future economic and social development.
However, the process of health improvement is not a single-dimensional linear advancement, but a multidimensional process that requires simultaneous attention to both health levels and health equity [3]. This means that while pursuing the overall improvement of health levels, it is also essential to ensure that everyone can equally access health services and resources. Universal health coverage emphasizes that everyone should be able to obtain the high-quality health services they need without financial hardship. This is not only about individual health rights but also the foundation for achieving overall improvements in societal health [2].
The World Health Organization (WHO) defines health as a state of complete physical, mental, and social well-being [4]. There are diverse health measurement indicators, including subjective and objective indicators. Objective indicators assess residents’ physiological and psychological parameters, including aspects such as physical function, treatment status, and medical history (e.g., mortality, morbidity). Subjective indicators reflect residents’ self-assessments of their health, typically represented in the form of self-rated health scores. With increasing emphasis on people-centered care, traditional health measurement indicators can no longer fully and accurately reflect health status [5]. The health-related quality of life (HRQoL) is a multifaceted concept that includes social functioning and physical and mental health status [6]. It is defined as ‘how well a person functions in their life and their perceived well-being in physical, mental, and social domains of health’ [7]. HRQoL, as a comprehensive method of evaluating health status, has played an irreplaceable role in recent years in clinical treatment, pharmaceutical research, preventive health care, and health economic evaluation. HRQoL has been widely used as a population health outcome measure in international literature [8, 9]. The EQ-5D family is perhaps the most commonly used instrument in assessing HRQoL [10].
Researchers have increasingly incorporated HRQoL into composite health metrics such as disability-adjusted life years (DALYs) to better capture population health outcomes [11]. The Global Burden of Disease (GBD) study has been instrumental in employing these indicators to explore causes of death, risk factors, and other determinants of health on a global scale [12]. However, significant gaps remain, particularly in integrating both health level and health equity perspectives. Most existing research focuses on single dimensions or equity alone, without a holistic approach. Research on health inequalities typically focuses on objective indicators such as disease prevalence [11, 13], BMI [14], and maternal and infant mortality rates [15], although there are emerging studies using subjective indicators like self-rated health [3].
This study addresses the gap in the literature by measuring changes in the level and equality of HRQoL in mainland China over the period of the COVID-19 pandemic from 2021 to 2023. The effect of the COVID-19 pandemic has been remarkable on a global scale. Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing previous decreasing trends [16]. However, there is a notable lack of research on recent HRQoL trends, especially the national trends associated with the COVID-19 pandemic [17, 18], despite some localized studies [19] in China.
Methods
Study setting
This study was conducted in mainland China during the COVID-19 pandemic. China adopted a phased approach to controlling the spread of the virus. From January to April 2020, strict containment measures were implemented, including a full lockdown of Wuhan. This was followed by a nationwide strategy of rapid responses to local outbreaks. In 2021 and 2022, China pursued a Dynamic Zero-COVID strategy, characterized by routine mass testing, the use of digital health codes, localized lockdowns, and strict quarantine protocols, all aimed at the early detection and containment of outbreaks. In December 2022, these measures were relaxed, and COVID-19 was downgraded to a Category B infectious disease, marking the end of the Dynamic Zero-COVID phase and the beginning of the country’s reopening. The year 2023 subsequently saw a surge in COVID-19 infections [20, 21].
Design
This study follows the STROBE reporting guidelines for cross-sectional studies (Supplementary file S1). Data were extracted from the Psychology and Behavior Investigation of Chinese Residents (PBICR), a nationally representative annual survey conducted by the School of Public Health of Peking University, China [22, 23]. PBICR collected data regarding individual sociodemographic characteristics, personal health and behaviors, and family and social environments. Three waves of PBICR have been conducted: from July 10th to September 15th in 2021, from June 20th to August 31st in 2022, and from June 20th to August 31st in 2023.
Data collection
PBICR data were collected through household visits conducted by data collection teams composed of higher-degree research students skilled in communication and teamwork. Each study participant was invited to self-complete the online survey through the platform Wen Juan Xing (https://www.wjx.cn/). Each team of investigators was responsible for collecting 100–200 questionnaires, with each team member contributing 30–90. Investigators were permitted to conduct household visits for data collection provided they held a green health code (indicating a negative nucleic acid test result) and the survey community was not under lockdown. For study participants who were under quarantine, data were collected through online video interviews. Eligible participants included those who were 12 years or older (restricted to 18 years or older in 2023), resided in the survey location permanently with no more than a one-month absence, and were able to understand the survey questions and provide informed consent. Those with serious mental health disorders, cognitive impairment, or prior involvement in other similar research projects were excluded.
Population and sample
The PBICR adopted a multi-stage sampling strategy based on the principle of probability proportional to size (PPS), followed by random selection and quota allocation [22, 23]. Approximately 780 residential communities were selected from 202 districts or counties across 31 provinces and regions in mainland China (22 provinces, 4 centrally administered municipalities, and 5 autonomous regions).
In the first stage, capital cities and centrally administered municipalities were purposively included. Additionally, between 1 and 12 other cities within each province or autonomous region were randomly selected using a random number table, with the number of cities sampled proportional to the provincial population size. This PPS approach resulted in the selection of 120 cities in 2021, 148 cities in 2022, and 150 cities in 2023.
In the second stage, within each selected city, between 6 and 36 communities were randomly chosen, again using a random number table. The number of communities sampled in each city was determined by its population size, following the PPS principle, leading to the selection of approximately 780 to 800 communities overall.
In the third stage, a sampling quota was assigned to each community based on the overall sample size requirements and the resident population size of each community.
A total of 11,709 participants in 2021, 31,626 in 2022, and 48,485 in 2023 were recruited for the survey, with 40, 177, and 816 individuals refusing to provide informed consent, respectively. Logic checks excluded an additional 638 responses in 2021, 943 in 2022, and 1,839 in 2023 due to extremely short response times, logical inconsistencies, duplicate entries, and missing values in key data.
To ensure comparability, the study restricted participants to those aged 19 years and older, as 18-year-old participants could not be identified separately in the 2021 dataset, and the 2023 survey was limited to individuals aged 18 years or older. This resulted in the removal of 1,065 responses in 2021, 2,161 in 2022, and 605 in 2023. Additionally, participants with incomplete address information or originating from outside mainland China were excluded (3 in 2021, 64 in 2022, and 222 in 2023). Consequently, the final sample included 9,963 participants in 2021, 28,280 participants in 2022, and 45,003 participants in 2023 for data analyses (Fig. 1). More details regarding the PBICR dataset are available in the metadata registry at https://wwwx-mol.com/groups/pbicr.
HRQoL is the primary health outcome of interest in this study, which was measured by the EQ-5D-5 L developed by the EuroQol Group [24]. It is a brief, self-reported generic measure of current health that consists of five dimensions (Mobility, Self-Care, Usual Activities, Pain/Discomfort, and Anxiety/Depression), with each dimension rated on a five-level scale ranging from “no problem” to “extreme difficulty” [10]. Compared to its predecessor, the EQ-5D-3L, the EQ-5D-5L has stronger discriminatory power and better convergent validity with a lower ceiling effect [25, 26].
The reliability and validity of the Chinese version of EQ-5D instruments have been demonstrated, including a population value set for estimating the utility index (UI) [27, 28]. Efforts have been made to establish EQ-5D norms for general health status, and some studies have examined HRQoL inequalities in specific regions or populations [9, 29, 30].
The EQ-5D-5 L also contains a vertical EuroQol visual analog scale (EQ-VAS), ranging from 0 (the worst imaginable health) to 100 (the best imaginable health). And the EQ-VAS represents the respondents’ perspective to record their own self-rated health [10, 27].
Independent variables
The level and equality of HRQoL are determined by many factors, including biological, social, and economic factors [31, 32]. The action framework for social determinants of health identifies direct pathogenic factors, individual behaviors, and environmental influences as causes of health outcome disparities. This study categorized variables into seven distinct categories, based on the health determinants model [33, 34] and the health equity model [35], which addresses health disparities under different social contexts, such as political, economic, and cultural conditions.
(1)
Individual demographic characteristics: Gender (male, female) and age (19–30, 31–40, 41–50, 51–60, 61–70, 71 + years).
(2)
Individual socio-economic characteristics: Educational attainment (illiteracy or elementary, junior middle school, high school, tertiary education), marital status (unmarried, married, divorced/widowed), employment status (employed, student, retired, others), health insurance coverage (no, yes), and per capita household income (Chinese Yuan). Per capita monthly household income data were converted into quintile rankings within each province (lowest, lower, middle, higher, highest) to enable regionally adjusted data analysis.
(3)
Individual health literacy: Measured by the validated SF Health Literacy Survey questionnaire (low, medium, high) [22, 36].
(4)
Individual health behavior: Smoking (no, yes) and alcohol consumption (no, yes).
(5)
Individual health status: Chronic conditions measured by a checklist of diseases diagnosed by a doctor (0, 1, 2 or more), body mass index (BMI) (underweight: <18.5 kg/m2, normal: 18.5 kg/m²≤BMI < 24 kg/m², overweight: 24 kg/m²≤BMI < 28 kg/m², obesity: ≥28 kg/m²), and five personality traits (extraversion, agreeableness, conscientiousness, nervousness, openness) measured by the Big Five Inventory (10 items) [37].
(6)
Family health: Measured by the validated Family Health Scale-Short Form (very poor, poor, good, very good) [22, 38].
(7)
Social support: Measured by the validated Perceived Social Support Scale (low, medium, high) [22, 39] and residential environments indicated by region (eastern, central, western) and residency (rural, urban).
Data analysis
To mitigate potential biases arising from the quota sampling method and nonresponses, the collected data were calibrated by adjusting for location, population size, sex, and age distribution. This approach not only ensures the generation of nationally representative data but also enhances comparability across different years. Previous studies have highlighted significant disparities in HRQoL between urban and rural populations in China [44, 45]. To account for these differences, age-gender-urban/rural weights, derived from the 2020 China Census data, were applied during data calibration (Supplementary File S2) for statistical analysis. All subsequent analyses, including the OLS regression models, the calculation of the EI, and the RIF decomposition, were conducted using these calibrated sampling weights to ensure unbiased and representative estimates.
Level of HRQoL
Percentages of respondents reporting health problems were calculated. The Chinese value set developed by Luo et al. [28] was used to convert the reported problems into a utility index (UI) score for each respondent, which ranges from − 0.391 to 1.000, with 1.000 indicating the best possible health and a negative score indicating a state worse than death. The EQ-VAS was scored from 0 to 100, with a higher score indicating a higher level of perceived overall health. Weighted mean values and standard deviations of UI and EQ-VAS scores were calculated.
Ordinary Least Squares (OLS) regression models were developed to determine the factors associated with UI (or EQ-VAS) scores (y).
where \(\:{X}_{1}\) to \(\:{X}_{7}\) indicate the seven categories of HRQoL determinants tested in this study, and \(\:{X}_{8}\) represents the variable of year. \(\:\epsilon\:\) stands for the error term.
To quantify the relative contributions of different determinants to the variation in HRQoL, we applied the Shapley decomposition method. Originally proposed by Lloyd Shapley, this approach decomposes the overall explanatory power of a regression model, as measured by the coefficient of determination (R²), into the individual contributions of each explanatory variable. It provides an equitable assessment of each variable’s importance in explaining the variance of the dependent variable by considering all possible permutations of variable entry into the model [40].
The Shapley decomposition method has been widely used in health inequality research [41]. In our analysis, it was applied to the OLS regression models of both EQ-UI and EQ-VAS scores to evaluate the contributions of various categories of HRQoL determinants, as well as the survey year, to the total explained variance.
Inequality of HRQoL
Inequality of HRQoL was defined as systematic variations between socioeconomic groups in the EQ-UI and EQ-VAS indicators [42]. It was assessed using the Erreygers Index (EI), a widely recognized metric in health inequality research [43]. The EI, an adaptation of the traditional concentration index (CI) proposed by Erreygers [44], provides a more accurate reflection of inequality [44, 45]. It ranges from − 1 to + 1, where 0 indicates the absence of income-related inequality. A positive EI reflects pro-rich inequality, while a negative EI reflects pro-poor inequality [44, 46].
where \(\:{h}_{i}\) and \(\:{y}_{i}\) denote the UI (or EQ-VAS) score and income of the i-th individual, respectively. \(\:n\) represents the sample size. \(\:{Max}_{h}\) and \(\:{Min}_{h}\:\)represent the maximum and minimum scores of UI (or EQ-VAS) in the study population. \(\:\sum\:_{i=1}^{n}{z}_{i}{h}_{i}\) expresses the rank-dependence character, which is a weighted UI (or EQ-VAS) sum of all individuals.
\(\:{{Z}_{i}=\frac{n+1}{2}-{\lambda\:}_{i},\:\:where\:Z}_{i}\) and \(\:{\lambda\:}_{i}\) represent the income rank deviation and the income rank of individual \(\:i\), respectively. A positive sign of \(\:{Z}_{i}\) indicates the group of the rich, while a negative sign of \(\:{Z}_{i}\) indicates the group of the poor. A zero \(\:{Z}_{i}\) means neither rich nor poor. The absolute value of the weight increase linearly with the distance of the rank from the middle [44].
This study employed the RIF-EI-OLS model to determine the marginal effect of each explanatory variable on HRQoL inequality. This model, a novel decomposition method proposed by Heckley in 2016, is derived from the influence function (IF) [47]. The RIF-EI-OLS method utilizes the recentered influence function (RIF) estimates of the health inequality index to determine the relationship between the RIF and explanatory variables. By establishing a regression function between the health inequality index and the explanatory variables, this method enables causal identification [43]. Compared to the traditional Wagstaff decomposition method, this method requires fewer and less restrictive assumptions. Meanwhile, this decomposition approach explains the causes of socioeconomic-related health inequality by directly decomposing the weighted covariance of health and socioeconomic rank, making estimation straightforward and results easy to interpret [47, 48].
The method involves two steps. The first step calculates the RIF (Recentered Influence Function) for the EI, which quantifies the contribution of each observation to the index. The RIF function uses the global statistic, EI, as a baseline and, through the influence function, facilitates a precise mapping from the aggregate measure to individual-level impacts. Specifically, the RIF for an individual observation with respect to the EI can be expressed as:
\(\:F\) is the distribution function of the health variable, and \(\:IF({h}_{i};EI,F)\)represents the influence function of the observation \(\:{h}_{i}\) on the EI. By capturing the marginal contribution of individual observations to the EI, the RIF function bridges the global index and individual-level impacts, making it a powerful tool for inequality decomposition.
In the second step, the calculated RIF values are regressed on a set of explanatory variables using ordinary least squares (OLS) to estimate their marginal effects on the EI. The regression coefficients directly quantify how each explanatory variable contributes to health inequalities. The regression model is specified as:
where \(\:{X}_{1}\) to \(\:{X}_{7}\) indicate the seven categories of EI determinants tested in this study, and \(\:{X}_{8}\) represents the variable of year. γ is the vector of coefficients, representing the marginal effects of the covariates on the EI. ε stands for the error term.
UI (or VAS) - EI composite index
The trade-off between equity and efficiency in health promotion has been a longstanding topic of academic inquiry. Two fundamental objectives of health systems are to maximize overall population health gains and to minimize unfair health inequalities [49]. In this study, we developed a composite index combining HRQoL (UI or VAS) and equity (EI), drawing inspiration from the universal health coverage framework [50]. To ensure consistency in interpretation, we transformed the equity component to 1−|EI|, so that higher values represent greater equity. This adjustment aligns the direction of change for both dimensions, allowing the composite index to range from 0 to 100, with higher scores indicating better population health and greater equity. This unified scale facilitates a clearer visualization of the balance between efficiency and equity across years. The formula is as follows:
Frequency distributions and weighted means (standard deviations) were used to describe nominal/ordinal and continuous variables, respectively. All statistical analyses were conducted using Stata IC 16.0. The practical implementation of RIF-EI-OLS regression decomposition is straightforward with software such as Stata [48]. A p-value < 0.05 was considered statistically significant.
We present the findings related to the EQ-UI scores in the main document, while the EQ-VAS results are presented in the supplementary files.
Ethical considerations
This study involved human participants and was approved by the Ethics Research Committee of the Health Culture Research Centre of Shaanxi (JKWH-2021-01/JKWH-2022-02) and Shandong Provincial Hospital (SWYX: NO.2023 − 198). Implied informed consent was obtained prior to each survey. Participants gave informed consent to participate in the study before proceeding to the online survey.
Results
Characteristics of respondents
The study sample was biased towards the most populous eastern developed zone (38.47%) and the least populated western underdeveloped zone (37.77%), compared to the central developing zone (23.76%). About 29.22% of respondents resided in rural areas (Table 1).
Table 1
Characteristics of study participants
Variables
2021
2021(weighted)
2022
2022(weighted)
2023
2023(weighted)
Total
Total(weighted)
N
%
N
%
N
%
N
%
N
%
N
%
N
%
N
%
Individual physiological characteristics
Gender
Male
4591
46.08
5035
50.54
12,162
43.01
14,305
50.58
20,197
44.88
22,764
50.58
36,950
44.39
42,025
50.48
Female
5372
53.92
4927
49.46
16,118
56.99
13,975
49.42
24,806
55.12
22,239
49.42
46,296
55.61
41,221
49.52
Age(years)
19–30
3599
36.12
1880
18.87
13,012
46.01
5334
18.86
21,241
47.20
8489
18.86
37,852
45.47
15,765
18.94
31–40
1732
17.38
1947
19.55
3637
12.86
5530
19.55
6041
13.42
8800
19.55
11,410
13.71
16,245
19.51
41–50
2480
24.89
1957
19.64
4334
15.33
5555
19.64
7377
16.39
8840
19.64
14,191
17.05
16,367
19.66
51–60
1006
10.10
1899
19.07
2935
10.38
5393
19.07
5117
11.37
8582
19.07
9058
10.88
15,863
19.06
61–70
513
5.15
1326
13.31
2462
8.71
3762
13.30
2878
6.40
5987
13.30
5853
7.03
11,054
13.28
≥ 71
633
6.35
953
9.57
1900
6.72
2705
9.56
2349
5.22
4304
9.56
4882
5.86
7952
9.55
Individual socio-economic characteristics
Educational attainment
Illiteracy/elementary
1015
10.19
2105
21.12
3323
11.75
6250
22.10
4798
10.66
9697
21.55
9136
10.97
18,016
21.64
Junior middle school
1224
12.29
1885
18.92
3043
10.76
5070
17.93
5467
12.15
8976
19.95
9734
11.69
15,988
19.21
High school
1596
16.02
1712
17.18
6493
22.96
5837
20.64
9346
20.77
9194
20.43
17,435
20.94
16,781
20.16
Tertiary education
6128
61.51
4261
42.77
15,421
54.53
11,122
39.33
25,392
56.42
17,136
38.08
46,941
56.39
32,461
38.99
Marital status
Unmarried
3297
33.09
2055
20.63
13,094
46.30
6693
23.67
21,668
48.15
11,071
24.60
38,059
45.72
19,851
23.85
Married
6224
62.47
7246
72.73
14,102
49.87
20,007
70.75
21,420
47.60
30,802
68.44
41,746
50.15
58,067
69.75
Divorced/widowed
442
4.44
662
6.65
1084
3.83
1580
5.59
1915
4.26
3131
6.96
3441
4.13
5327
6.40
Employment status
Employed
4624
46.41
3713
37.26
9423
33.32
10,210
36.10
16,007
35.57
16,120
35.82
30,054
36.10
29,942
35.97
Student
2270
22.78
1331
13.36
10,196
36.05
4535
16.04
15,270
33.93
6582
14.63
27,736
33.32
12,512
15.03
Retired
883
8.86
1320
13.25
2886
10.21
3853
13.62
4487
9.97
7458
16.57
8256
9.92
12,613
15.15
Others
2186
21.94
3600
36.13
5775
20.42
9682
34.24
9239
20.53
14,843
32.98
17,200
20.66
28,179
33.85
Basic social health insurance
No
2147
21.55
1997
20.04
2586
9.14
2216
7.84
3256
7.24
2766
6.15
7989
9.60
6993
8.40
Yes
7816
78.45
7966
79.96
25,694
90.86
26,064
92.16
41,747
92.76
42,237
93.85
75,257
90.40
76,253
91.60
Commercial medical insurance
No
9746
97.82
9797
98.34
26,889
95.08
27,119
95.89
42,827
95.16
43,052
95.66
79,462
95.45
79,928
96.01
Yes
217
2.18
166
1.66
1391
4.92
1161
4.11
2176
4.84
1951
4.34
3784
4.55
3318
3.99
Household income ranking
Lowest
3229
32.41
4094
41.09
7672
27.13
9463
33.46
12,319
27.37
14,406
32.01
23,220
27.89
27,806
33.40
Lower
1855
18.62
1804
18.11
5496
19.43
5939
21.00
9119
20.26
9649
21.44
16,470
19.78
17,499
21.02
Middle
1771
17.78
1630
16.36
5856
20.71
5287
18.69
8480
18.84
8336
18.52
16,107
19.35
15,266
18.34
Higher
1413
14.18
1192
11.96
4862
17.19
4283
15.15
7962
17.69
6987
15.53
14,237
17.10
12,455
14.96
Highest
1695
17.01
1243
12.48
4394
15.54
3308
11.70
7123
15.83
5625
12.50
13,212
15.87
10,220
12.28
Individual health literacy
Health literacy
Low
315
3.16
443
4.45
1467
5.19
1930
6.82
11,697
25.99
14,662
32.58
13,479
16.19
17,086
20.52
Medium
6308
63.31
6716
67.41
16,476
58.26
17,631
62.35
25,570
56.82
23,804
52.89
48,354
58.09
48,167
57.86
High
3340
33.52
2804
28.14
10,337
36.55
8719
30.83
7736
17.19
6537
14.52
21,413
25.72
17,993
21.61
Individual health behavior
Smoking
No
8583
86.15
8252
82.83
24,544
86.79
23,155
81.88
38,285
85.07
36,296
80.65
71,412
85.78
67,719
81.35
Yes
1380
13.85
1711
17.17
3736
13.21
5125
18.12
6718
14.93
8707
19.35
11,834
14.22
15,527
18.65
Alcohol drinking
No
5768
57.89
5913
59.35
22,143
78.30
21,963
77.66
34,013
75.58
34,150
75.88
61,924
74.39
62,050
74.54
Yes
4195
42.11
4050
40.65
6137
21.70
6317
22.34
10,990
24.42
10,853
24.12
21,322
25.61
21,196
25.46
Individual health status
Chronic conditions
0
7959
79.89
7193
72.20
21,662
76.60
19,954
70.56
32,868
73.04
27,590
61.31
62,489
75.07
54,752
65.77
1
1347
13.52
1765
17.72
4465
15.79
5295
18.72
7426
16.50
9858
21.91
13,238
15.90
16,924
20.33
2ormore
657
6.59
1004
10.08
2153
7.61
3031
10.72
4709
10.46
7555
16.79
7519
9.03
11,570
13.90
Body mass index (BMI)
Underweight
1232
12.37
1030
10.34
5099
18.03
3866
13.67
6220
13.82
4669
10.38
12,551
15.08
9578
11.51
Normal
6154
61.77
6045
60.68
16,808
59.43
16,748
59.22
27,772
61.71
27,542
61.20
50,734
60.94
50,393
60.54
Overweight
2175
21.83
2416
24.25
5119
18.10
6281
22.21
8842
19.65
10,530
23.40
16,136
19.38
19,174
23.03
Obesity
402
4.03
472
4.74
1254
4.43
1385
4.90
2169
4.82
2262
5.03
3825
4.59
4101
4.93
Extraversion
6.26 ± 1.58
6.23 ± 1.54
6.22 ± 1.63
6.18 ± 1.54
6.21 ± 1.60
6.20 ± 1.55
6.22 ± 1.61
6.20 ± 1.55
Agreeableness
7.00 ± 1.49
6.97 ± 1.50
6.96 ± 1.48
6.95 ± 1.46
6.83 ± 1.41
6.86 ± 1.43
6.89 ± 1.45
6.90 ± 1.45
Conscientiousness
6.91 ± 1.60
7.03 ± 1.58
6.67 ± 1.64
6.89 ± 1.60
6.64 ± 1.55
6.87 ± 1.54
6.68 ± 1.59
6.89 ± 1.57
Nervousness
5.74 ± 1.49
5.69 ± 1.46
5.82 ± 1.56
5.71 ± 1.48
5.85 ± 1.44
5.75 ± 1.39
5.82 ± 1.49
5.73 ± 1.43
Openness
6.41 ± 1.52
6.16 ± 1.49
6.53 ± 1.56
6.24 ± 1.49
6.35 ± 1.52
6.05 ± 1.47
6.42 ± 1.53
6.13 ± 1.48
Family characteristics
Family health
Very poor
12
0.12
12
0.12
34
0.12
35
0.12
57
0.13
68
0.15
103
0.12
117
0.14
Poor
594
5.96
663
6.66
2158
7.63
2352
8.32
2273
5.05
2620
5.82
5025
6.04
5628
6.76
Good
5190
52.09
5275
52.94
13,293
47.00
14,152
50.04
20,535
45.63
20,985
46.63
39,018
46.87
40,487
48.63
Very good
4167
41.82
4013
40.27
12,795
45.24
11,741
41.52
22,138
49.19
21,329
47.40
39,100
46.97
37,015
44.46
Social characteristics
Social support
Low
432
4.34
447
4.49
2302
8.14
2399
8.48
3474
7.72
3418
7.59
6208
7.46
6277
7.54
Medium
5061
50.80
5219
52.38
13,000
45.97
13,183
46.62
19,428
43.17
19,193
42.65
37,489
45.03
37,669
45.25
High
4470
44.87
4297
43.13
12,978
45.89
12,698
44.90
22,101
49.11
22,392
49.76
39,549
47.51
39,300
47.21
Region
Eastern
5096
51.15
5019
50.38
9601
33.95
8540
30.20
17,329
38.51
17,442
38.76
32,026
38.47
31,329
37.63
Central
2561
25.71
2531
25.40
6855
24.24
6657
23.54
10,362
23.03
10,165
22.59
19,778
23.76
19,211
23.08
Western
2306
23.15
2413
24.22
11,824
41.81
13,083
46.26
17,312
38.47
17,395
38.65
31,442
37.77
32,707
39.29
Residency
Rural
2711
27.21
5789
58.10
7804
27.60
16,436
58.12
13,809
30.68
26,155
58.12
24,324
29.22
48,299
58.02
Urban
7252
72.79
4174
41.90
20,476
72.40
11,844
41.88
31,194
69.32
18,847
41.88
58,922
70.78
34,947
41.98
Total
9963
100.00
9963
100.00
28,280
100.00
28,280
100.00
45,003
100.00
45,003
100.00
83,246
100.00
83,246
100.00
Overall, 13% of respondents were older than 60 years, and more than half were female (55.61%), received tertiary education (56.39%), and were married (50.15%) at the time of the survey. About 36% were employed. Nearly half of the respondents (47.67%) fell into the lowest or lower quintile of per capita household income within their province or autonomous region. The vast majority resided in urban areas (70.78%), enrolled in the basic social health insurance (90.40%), and reported no chronic conditions (75.07%). Low levels of social support were rated by less than 10% of respondents.
Around 60% of respondents had a normal BMI in all three waves of surveys. The vast majority reported good or very good family health (> 90%) and were not smoking (85.78%) nor drinking alcohol (74.39%) at the time of the survey. The respondents reported higher levels of agreeableness (6.89 ± 1.45) and conscientiousness (6.68 ± 1.59) in personality features than others.
Utility index
The weighted average UI score of respondents was highest in 2021, reaching 0.9363 (SD = 0.1389), before declining to 0.9332 (SD = 0.1524) in 2022 and further to 0.9244 (SD = 0.1546) in 2023, indicating a downward trend in HRQoL over time (β=-0.0143~-0.0081, P < 0.001). The most frequently reported problem was anxiety/depression (24.86%~28.03%), followed by pain/discomfort (24.02%~27.41%), mobility (11.06%~13.53%), usual activities (8.67%~11.23%), and self-care (6.59%~8.80%) (Supplemental file S3).
Pro-rich inequality in UI was evident as indicated by the positive value of EI, with lower UI scores being concentrated among those with lower income. The EI of UI decreased from 0.0703 in 2021 to 0.0635 in 2022 (β=-0.0105, P < 0.01), before bouncing back in 2023. However, the UI-EI composite index was the lowest in 2023 (92.4849), compared with that in 2021 (93.2993) and in 2022 (93.4837) (Table 2).
Table 2
Changes of EQ-5D-5 L utility index (UI) and Erreyger index (EI) over years (weighted) measured by regression coefficient (β)
Overall, the respondents who had better health, higher socioeconomic status, higher health literacy, and supportive living environments tended to have higher UI but lower EI scores (Table 3).
Table 3
EQ-5D-5 L utility index (UI) (weighted mean ± standard deviation), Erreyger index (EI) scores and UI-EI index by characteristics of respondents
Variables
2021
2022
2023
UI
SD
EI
UI-EI
UI
SD
EI
UI-EI
UI
SD
EI
UI-EI
Individual physiological characteristics
Gender
Male
0.9414
0.1350
0.0660
93.7654
0.9308
0.1641
0.0643
93.3228
0.9249
0.1597
0.0734
92.5759
Female
0.9311
0.1426
0.0738
92.8610
0.9356
0.1393
0.0629
93.6337
0.9239
0.1492
0.0764
92.3754
Age (years)
19–30
0.9594
0.1063
0.0351
96.2175
0.9256
0.1735
0.0632
93.1190
0.9406
0.1390
0.0443
94.8118
31–40
0.9663
0.0962
0.0315
96.7426
0.9410
0.1536
0.0529
94.4054
0.9446
0.1363
0.0503
94.7177
41–50
0.9551
0.1107
0.0427
95.6206
0.9462
0.1356
0.0522
94.6971
0.9473
0.1228
0.0536
94.6848
51–60
0.9397
0.1251
0.0631
93.8289
0.9526
0.1176
0.0543
94.9156
0.9288
0.1562
0.0466
94.1051
61–70
0.8911
0.1826
0.0976
89.6722
0.9326
0.1379
0.0562
93.8211
0.8969
0.1673
0.1048
89.6063
≥ 71
0.8465
0.2080
0.1574
84.4544
0.8674
0.1942
0.1109
87.8190
0.8334
0.2083
0.1507
84.1303
Individual socio-economic characteristics
Educational attainment
Illiteracy or elementary
0.8812
0.1926
0.1489
86.6045
0.9188
0.1525
0.0942
91.2256
0.8884
0.1832
0.1214
88.3523
Junior middle school
0.9424
0.1158
0.0541
94.4164
0.9485
0.1299
0.0546
94.6953
0.9347
0.1431
0.0567
93.8952
High school
0.9452
0.1240
0.0466
94.9305
0.9401
0.1475
0.0643
93.7885
0.9300
0.1496
0.0629
93.3525
Tertiary education
0.9571
0.1127
0.0320
96.2569
0.9306
0.1631
0.0562
93.7220
0.9364
0.1417
0.0552
94.0594
Marital status
Unmarried
0.9462
0.1396
0.0511
94.7559
0.9168
0.1843
0.0718
92.2480
0.9264
0.1605
0.0651
93.0670
Married
0.9408
0.1289
0.0631
93.8856
0.9445
0.1297
0.0532
94.5649
0.9330
0.1399
0.0654
93.3796
Divorced/widowed
0.8554
0.2022
0.1664
84.4413
0.8586
0.2245
0.1366
86.0987
0.8325
0.2247
0.1584
83.7032
Employment status
Employed
0.9666
0.0833
0.0251
97.0754
0.9544
0.1221
0.0347
95.9809
0.9445
0.1315
0.0481
94.8224
Student
0.9459
0.1400
0.0374
95.4194
0.9119
0.1925
0.0747
91.8603
0.9339
0.1520
0.0498
94.2016
Retired
0.9021
0.1698
0.0793
91.1338
0.9033
0.1692
0.0761
91.3542
0.8772
0.1859
0.1127
88.2204
Others
0.9139
0.1628
0.1148
89.9461
0.9327
0.1493
0.0859
92.3353
0.9221
0.1564
0.0905
91.5776
Basic social health insurance
No
0.9214
0.1644
0.1018
90.9698
0.8898
0.2349
0.1164
88.6683
0.8968
0.2129
0.0652
91.5604
Yes
0.9400
0.1315
0.0622
93.8919
0.9369
0.1426
0.0591
93.8900
0.9262
0.1498
0.0752
92.5506
Commercial medical insurance
No
0.9364
0.1387
0.0708
93.2793
0.9346
0.1504
0.0656
93.4499
0.9260
0.1507
0.0749
92.5532
Yes
0.9276
0.1531
0.0487
93.9357
0.9008
0.1896
0.0685
91.6044
0.8901
0.2204
0.1233
88.3375
Per capita monthly household income (Yuan)
Lowest
0.9185
0.1598
-
-
0.9173
0.1740
-
-
0.9062
0.1680
-
-
Lower
0.9396
0.1307
-
-
0.9373
0.1326
-
-
0.9281
0.1455
-
-
Middle
0.9487
0.1297
-
-
0.9450
0.1337
-
-
0.9384
0.1367
-
-
Higher
0.9541
0.1077
-
-
0.9469
0.1349
-
-
0.9297
0.1542
-
-
Highest
0.9565
0.1032
-
-
0.9345
0.1643
-
-
0.9374
0.1550
-
-
Individual health literacy
Health literacy
Low
0.8126
0.2683
0.2006
80.5968
0.8431
0.2447
0.1395
85.1743
0.8949
0.1897
0.0986
89.8183
Medium
0.9312
0.1386
0.0695
93.0888
0.9303
0.1503
0.0647
93.2791
0.9405
0.1263
0.0578
94.1359
High
0.9678
0.0878
0.0303
96.8775
0.9589
0.1178
0.0303
96.4288
0.9319
0.1510
0.0623
93.4783
Individual health behavior
Smoking
No
0.9366
0.1378
0.0678
93.4420
0.9386
0.1452
0.0625
93.8087
0.9324
0.1414
0.0679
93.2293
Yes
0.9345
0.1443
0.0820
92.6201
0.9085
0.1792
0.0648
92.1741
0.8909
0.1970
0.1017
89.4595
Alcohol drinking
No
0.9352
0.1398
0.0718
93.1701
0.9393
0.1400
0.0609
93.9221
0.9261
0.1520
0.0745
92.5818
Yes
0.9378
0.1376
0.0679
93.4948
0.9117
0.1876
0.0747
91.8492
0.9191
0.1622
0.0760
92.1550
Individual health status
Chronic conditions
0
0.9617
0.1037
0.0365
96.2619
0.9513
0.1352
0.0436
95.3848
0.9590
0.1133
0.0391
95.9939
1
0.8976
0.1705
0.1003
89.8681
0.9144
0.1577
0.0697
92.2304
0.9042
0.1622
0.0696
91.7235
2 or more
0.8217
0.2071
0.1699
82.5878
0.8465
0.2062
0.1307
85.7862
0.8244
0.2149
0.1514
83.6385
Body mass index (BMI)
Underweight
0.9157
0.1652
0.0662
92.4681
0.9143
0.1832
0.0831
91.5630
0.9031
0.1889
0.1046
89.9242
Normal
0.9424
0.1293
0.0663
93.8057
0.9354
0.1476
0.0601
93.7652
0.9290
0.1450
0.0667
93.1139
Overweight
0.9307
0.1470
0.0776
92.6509
0.9387
0.1455
0.0640
93.7363
0.9260
0.1528
0.0777
92.4116
Obesity
0.9311
0.1465
0.0860
92.2506
0.9337
0.1409
0.0502
94.1692
0.9055
0.1882
0.0888
90.8332
Family characteristics
Family health
Very poor
0.6564
0.3455
0.4655
59.2350
0.8818
0.1820
0.1680
85.6541
0.7783
0.3077
0.3647
70.3134
Poor
0.8815
0.2131
0.1136
88.3938
0.8442
0.2314
0.1068
86.8356
0.8001
0.2835
0.1287
83.4938
Good
0.9338
0.1421
0.0714
93.1212
0.9248
0.1687
0.0711
92.6845
0.9129
0.1661
0.0818
91.5530
Very good
0.9494
0.1122
0.0564
94.6495
0.9613
0.0912
0.0393
96.0976
0.9515
0.1013
0.0499
95.0800
Social characteristics
Social support
Low
0.8939
0.1955
0.1000
89.6973
0.8616
0.2281
0.1061
87.7611
0.8538
0.2512
0.1328
86.0476
Medium
0.9266
0.1517
0.0761
92.5254
0.9208
0.1605
0.0710
92.4885
0.9156
0.1563
0.0832
91.6231
High
0.9524
0.1107
0.0564
94.7951
0.9596
0.1154
0.0428
95.8372
0.9427
0.1277
0.0553
94.3688
Region
Eastern
0.9387
0.1387
0.0610
93.8857
0.9234
0.1608
0.0516
93.5856
0.9189
0.1643
0.0658
92.6521
Central
0.9327
0.1453
0.0854
92.3573
0.9350
0.1530
0.0623
93.6307
0.9369
0.1331
0.0760
93.0418
Western
0.9351
0.1323
0.0754
92.9808
0.9386
0.1460
0.0776
93.0477
0.9226
0.1558
0.0876
91.7487
Residency
Rural
0.9287
0.1502
0.0888
91.9888
0.9275
0.1626
0.0800
92.3732
0.9168
0.1676
0.0844
91.6208
Urban
0.9468
0.1207
0.0460
95.0408
0.9411
0.1365
0.0430
94.9011
0.9349
0.1337
0.0593
93.7780
Total
0.9363
0.1389
0.0703
93.2993
0.9332
0.1524
0.0635
93.4837
0.9244
0.1546
0.0747
92.4849
Male respondents had higher UI, lower EI scores and UI-EI composite index than their female counterparts in 2021 and 2023, but this was reversed in 2022. The UI scores declined by age, but the EI of UI scores increased by age. And the UI-EI composite index has the similar trend with the UI scores (Fig. 2).
Fig. 2
The EQ-5D-5 L utility index and Erreyger Index (EI) by year
The eastern developed and western under-developed zones had an upward trend in UI scores over the three years, compared with a downward trend in the central developing zone. The lowest EI was also found in the eastern developed zone. Meanwhile, the western under-developed zone experienced an upward trend in EI. The UI-EI composite index in the eastern region showed a decreasing trend, while the central and western regions showed a fluctuating trend during this three-years period. And in 2021, the UI-EI composite index was highest in the eastern region, while in 2022 and 2023, the central region had the highest UI-EI composite index.
Rural respondents had lower UI but higher EI scores than their urban counterparts. During these three years, the UI-EI composite index in urban areas consistently remained higher than in rural areas.
Determinants of utility index
The OLS regression showed that UI decreased by age (β=-0.0553~-0.0093, P < 0.05). Those who were married (β = 0.0180, P < 0.001), had a highest qualification of junior middle school (β = 0.0072, P < 0.05), were covered by basic health social insurance (β = 0.0155, P < 0.001), resided in urban (β = 0.0049, P < 0.001) and the western underdeveloped zone (β = 0.0044, P < 0.01), and reported higher health literacy (β = 0.0228 ~ 0.0257, P < 0.001) and higher social support (β = 0.0222 ~ 0.0300, P < 0.001) had higher UI scores than others. By contrast, being female (β=-0.0071, P < 0.001), smoking (β=-0.0196, P < 0.001), drinking alcohol (β=-0.0107, P < 0.001), and living with chronic conditions (β=-0.0989~-0.0417, P < 0.001) were associated with lower UI scores. Higher income was associated with higher UI scores (β = 0.0077 ~ 0.0123, P < 0.01), indicating pro-rich inequality (Table 4).
Table 4
Decomposition of contributors to EQ-5D-5 L utility index (UI) and Erreyger index (EI) scores (weighted)
Variables
UI
EI
OLS
Shapley decomposition
RIF-EI-OLS
Coef.
P value
Shapley value
con %
Coef.
P value
Individual physiological characteristics
0.0117
7.15%
Gender (Ref: male)
Female
-0.0071
0.0000
-0.0085
0.0030
Age (years) (Ref: 19–30)
31–40
-0.0114
0.0010
0.0093
0.1330
41–50
-0.0102
0.0080
0.0019
0.7850
51–60
-0.0093
0.0160
-0.0048
0.4910
61–70
-0.0146
0.0010
0.0091
0.2570
≥ 71
-0.0553
0.0000
0.0471
0.0000
Individual socio-economic characteristics
0.0183
11.15%
Educational attainment (Ref: illiteracy or elementary)
Junior middle school
0.0072
0.0030
-0.0229
0.0000
High school
0.0005
0.8640
-0.0138
0.0020
Tertiary education
-0.0073
0.0070
-0.0093
0.0640
Marital status (Ref: unmarried)
Married
0.0180
0.0000
-0.0043
0.5030
Divorced/widowed
-0.0284
0.0000
0.0220
0.0330
Employment status (Ref: employed)
Student
-0.0180
0.0000
0.0068
0.0530
Retired
-0.0088
0.0040
-0.0120
0.0840
Others
-0.0046
0.0170
-0.0191
0.0000
Basic social health insurance (Ref: no)
Yes
0.0155
0.0000
-0.0002
0.9700
Commercial medical insurance (Ref: no)
Yes
-0.0204
0.0000
-0.0222
0.0170
Household income ranking (Ref: lowest)
Lower
0.0101
0.0000
-0.0189
0.0000
Middle
0.0123
0.0000
-0.0130
0.0000
Higher
0.0090
0.0000
-0.0223
0.0000
Highest
0.0077
0.0020
-0.0189
0.0030
Individual health literacy
0.0077
4.68%
Health literacy (Ref: low)
Medium
0.0228
0.0000
-0.0116
0.0050
High
0.0257
0.0000
-0.0105
0.0400
Individual health behavior
0.0069
4.20%
Smoking (Ref: no)
Yes
-0.0196
0.0000
-0.0050
0.2440
Alcohol drinking (Ref: no)
0.0027
0.4370
Yes
-0.0107
0.0000
Individual health status
0.0604
36.82%
Chronic conditions (Ref:0)
1
-0.0417
0.0000
-0.0031
0.3470
2 or more
-0.0989
0.0000
0.0315
0.0000
Body mass index (BMI) (Ref: underweight)
Normal
0.0120
0.0000
-0.0080
0.0850
Overweight
0.0105
0.0000
-0.0078
0.1340
Obesity
0.0035
0.4080
-0.0184
0.0160
Extraversion
0.0018
0.0000
-0.0001
0.8540
Agreeableness
0.0020
0.0000
-0.0005
0.5590
Conscientiousness
0.0012
0.0140
0.0023
0.0060
Nervousness
-0.0055
0.0000
0.0020
0.0200
Openness
-0.0001
0.8700
0.0006
0.4050
Family characteristics
0.0259
15.81%
Family health (Ref: very poor)
Poor
0.0330
0.4010
-0.1349
0.0000
Good
0.0916
0.0190
-0.1319
0.0000
Very good
0.1096
0.0050
-0.1297
0.0010
Social characteristics
0.0099
6.03%
Social support (Ref: low)
Medium
0.0222
0.0000
-0.0023
0.7580
High
0.0300
0.0000
-0.0018
0.8120
Region (Ref: eastern)
Central
0.0028
0.1030
0.0134
0.0000
Western
0.0044
0.0060
0.0112
0.0000
Residency (Ref: rural)
Urban
0.0049
0.0000
0.0031
0.2520
Year (Ref: 2021)
0.0009
0.55%
2022
-0.0045
0.0480
-0.0040
0.3140
2023
-0.0022
0.2960
-0.0068
0.0710
The Shapley decomposition analysis showed that individual health was the largest contributor, accounting for 36.82% of variations in UI scores. This was followed by family characteristics (15.81%) and individual socio-economic characteristics (11.15%). The other determinants accounted for less than 10% of variations in UI scores for each category. The variable of year contributed to only 0.55% of variations in UI scores (Table 4).
The RIF-EI-OLS model showed that inequality in UI scores was explained by older age (β = 0.0471 for those older than 70 years, P < 0.001), marriage disruption (β = 0.0220 for those divorced or widowed, P < 0.05), and living with two or more chronic conditions (β = 0.0315, P < 0.001). By contrast, higher educational attainment (β=-0.0093~-0.0229, P < 0.1), better health literacy (β=-0.0116~-0.0105, P < 0.05) and having a good family health (β=-0.1349~-0.1297, P < 0.001) contributed negatively to inequality in UI scores. Conscientiousness (β = 0.0023, P < 0.05) and nervousness (β = 0.0020, P < 0.05) personality was associated with higher health inequality. Overall, increased income was associated with decreased inequality in UI scores (β=-0.0223~-0.0130, P < 0.01). Inequality in UI scores also varied across regions, with the central developing (β = 0.0134, P < 0.001) and the western underdeveloped zones (β = 0.0112, P < 0.001) featuring higher inequality compared with their eastern developed counterpart (Table 4).
EQ-VAS scores
Similar results for the EQ-VAS scores were found. The EQ-VAS scores showed a significant decreasing trend over time (β=-8.3268~-7.8634, P < 0.001). However, the EI of EQ-VAS exhibited an upward trend (β = 0.0172 ~ 0.0191, P < 0.05), indicating increasing inequality (Supplementary materials S4). Higher socioeconomic status, better health, higher health literacy, and supportive living environments were associated with higher EQ-VAS and lower EI scores (Supplementary materials S5). Senior age (> 70 years) and living with chronic conditions were associated with higher inequality in EQ-VAS, while higher health literacy, better family health, and higher social support were associated with lower inequality in EQ-VAS (Supplementary materials S6).
Discussion
This study examined trends in HRQoL from both a level and equity perspective, utilizing nationwide data from mainland China between 2021 and 2023. Our findings reveal a slight declining trend in both EQ-UI and EQ-VAS scores from 2021 to 2023, consistent with patterns observed in previous global studies [18, 51, 52]. However, the changes in UI scores (effect size = -0.058 to -0.022, both < 0.5) may not be of significant clinical importance [17, 53]. The mean weighted UI scores for the Chinese population ranged from 0.9244 to 0.9363 during this period, closely aligning with the 0.939 score reported in Tianjin in 2020 [54].
We observed an increase in the percentage of reported problems across the five dimensions of HRQoL, with pain/discomfort and usual activities showing the greatest change. Among these, anxiety/depression emerged as the most commonly reported issue, followed by pain/discomfort, which is consistent with findings from a study in China [55]. During the survey period, China implemented a strict “zero-COVID” or “dynamic zero-COVID” strategy, which included large-scale nucleic acid testing and lockdown measures in areas with outbreaks [20]. These prolonged measures restricted daily life and social interactions, potentially contributing to emotional distress and a decline in HRQoL [56].
The pro-rich inequality in HRQoL persisted in mainland China according to our study, with the EI for UI ranging from 0.0635 to 0.0747, which is consistent with previous studies conducted in China [3, 9, 32]. The EI in mainland China is higher than in Thailand [57] (0.024 in 2019) and Chile [58] (0.047 in 2013), but is much lower than Argentina [59] (0.1223 in 2013) and Iran [60] (0.133 in 2016). Despite the Chinese government’s efforts over the past few decades to narrow the wealth gap and rural-urban health disparity, concerns remain [61].
Despite the decline in EQ-UI scores between 2021 and 2023, inequality in UI decreased, as reflected by the EI values in 2022 and 2023—findings that are consistent with those of previous studies [19, 48]. However, the EI of EQ-VAS suggests a rise in health inequality over the same period. This discrepancy may indicate that the EQ-UI does not fully capture certain concerns reflected in residents’ VAS ratings, in particular among those with relatively lower income who were most impacted by the pandemic. Nonetheless, it remains essential to monitor the long-term trajectory of health inequality and implement targeted policy interventions to address disparities related to region, urban–rural residence, and income in China.
Overall, 2023 recorded the lowest composite index score, considering both UI and EI, compared to 2021 and 2022. Numerous factors contributed to changes in HRQoL and health inequalities, with income, health literacy, family health, chronic conditions, and residency identified as key determinants in our study. Globally, the Universal Health Coverage (UHC) service coverage index (SCI) has been increasing since 2000; however, the COVID-19 pandemic poses a significant threat to reversing two decades of progress [2].
Our research indicated that higher income can be a crucial factor in improving HRQoL and mitigating health inequalities, as supported by multiple studies [6, 29, 32]. Income also shapes health-seeking behaviors, health expectations, and other determinants of health [62, 63]. Unfortunately, evidence has shown that the COVID-19 pandemic has led to widespread income losses globally [64], further jeopardizing the health outcomes associated with COVID-19 [65, 66].
Education has been shown to improve HRQoL and promote health equity, as supported by previous studies [67, 68]. Individuals with higher educational attainment generally have better health literacy, greater access to health information [69], and more stable, higher-paying jobs, enabling families to accumulate health resources [70] that can buffer against health risks during the COVID-19 pandemic. Furthermore, the disruption of formal education during the pandemic disproportionately affected students from lower socioeconomic backgrounds, potentially exacerbating existing health inequalities [71].
We found that higher health literacy is a significant factor in increasing HRQoL and reducing health inequalities, consistent with previous studies [32, 72]. Higher health literacy is associated with healthier behaviors, including greater individual engagement in healthcare [32, 73‐75]. Conversely, lower health literacy is often linked with lower income [76]. The COVID-19 pandemic has underscored the importance of health literacy [74], particularly in combating misinformation and disinformation [77].
Regional and urban-rural health disparities have long been a concern in China, and this study further verifies their continuous existence. Urban residents have higher HRQoL but lower health inequality compared with their rural counterparts. The higher health inequality in rural China is likely associated with a lack of resources and weaker healthcare systems in these areas [48]. The eastern zone of mainland China, characterized by higher socioeconomic development, shows lower HRQoL but also lower health inequality, consistent with previous studies [9, 32, 48]. In contrast, the less developed zones exhibit higher health inequalities. These regional disparities are likely due to the greater levels of welfare and infrastructure support available in the eastern zone, although chronic conditions have become a more significant health concern there [78]. During the COVID-19 pandemic, regional disparities in health appear to have been reduced thanks to enhanced resource support from the government.
The findings of this study carry important policy implications and offer valuable insights. However, it is important to recognize that some of these findings may not be directly applicable to other countries due to China’s unique national circumstances. Despite rapid economic development and significant strengthening of its health system, income-related health inequality remains a major concern, and regional and urban-rural disparities persist, though some improvements have been made. The government should allocate more resources to disadvantaged populations, particularly those with lower income and educational attainment and those burdened by chronic conditions. Previous studies have shown that catastrophic health expenditure remains a significant concern for these groups in China [79].
Limitations
There are some potential limitations in this study worth noting. First, the 2021 PBICR does not allow for a precise breakdown of age, as individuals aged 12 to 18 years are grouped together. Therefore, the conclusions of this study may not be generalizable to all age populations. Second, the data do not capture potential behavioral changes related to COVID-19 policies, such as lockdown measures and region-specific policy adaptations. Additionally, the study may not account for all underlying factors affecting HRQoL and health inequality. Finally, the sampling methods resulted in an overrepresentation of the western underdeveloped zone, although we adjusted the results using population weights. As this study was conducted during the COVID-19 pandemic, future research should investigate the long-term trends in health inequality.
It is important to recognize that different health measurement instruments may yield varying results. Overall, the EQ-VAS results (Supplemental Files S3–S5) align with the patterns observed in the UI results. However, discrepancies emerge in the temporal trends of the EI when comparing findings based on UI and VAS. A potential explanation lies in the conceptual differences between the two measures: the VAS reflects individuals’ subjective evaluations of their general health status, which may be influenced by personal expectations and perceptions, whereas the UI captures health status based on standardized population-level valuations. As a result, individual assessments may not always align with values endorsed at the population level.
Conclusion
During the COVID-19 pandemic, residents of mainland China experienced a slight decline in HRQoL, alongside a reduction in UI inequality but an increase in VAS inequality in 2022 and 2023. Overall, 2023 recorded the lowest composite index score, which accounts for both UI and EI, compared to 2021 and 2022. Several key factors contributed to these changes, including socioeconomic status, chronic conditions, health literacy, and family health. Despite significant efforts by the Chinese government to develop infrastructure and expand universal health coverage, the pandemic may have hindered progress toward achieving healthcare equality.
Declarations
Ethics approval and consent to participate
Ethical approval was obtained from the Ethics Research Committee of the Health Culture Research Centre of Shaanxi (JKWH-2021-01/JKWH-2022-02) and Shandong Provincial Hospital (SWYX: NO.2023 − 198). Implied informed consent was obtained from all the study participants. All methods were carried out in accordance with relevant guidelines and regulations.
Consent for publication
Not applicable.
Competing interests
The authors have no relevant financial or nonfinancial interests to disclose.
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