Analysis of health-related quality of life (HRQL), its distribution, and its distribution by income in Japan, 1989 and 1998

Decomposing income-related inequality in health-related quality of life in mainland China: a national cross-sectional study

INTRODUCTION

Health equity is an important indicator measuring social development and solidarity. However, there is a paucity in nationwide studies into the inequity in health-related quality of life (HRQoL) in mainland China, in particular using the most recent data measuring HRQoL using the EuroQol 5-Dimension-5 Level (EQ-5D-5L). This study aimed to address the gap in the literature by estimating and decomposing income-related inequality of the utility index (UI) of EQ-5D-5L in mainland China.

METHODS

Data were extracted from the Psychology and Behaviour Investigation of Chinese Residents (2022), including 19 738 respondents over the age of 18 years. HRQoL was assessed by the UI of the EQ-5D-5L. Concentration index (CI) was calculated to measure the degree of income-related inequality in the UI. The contributions of individual, behavioural and context characteristics to the CI were estimated using the Wagstaff decomposition method.

RESULTS

The CI of the EQ-5D-5L UI reached 0.0103, indicating pro-rich inequality in HRQoL. Individual characteristics made the greatest contribution to the CI (57.68%), followed by context characteristics (0.60%) and health behaviours (-3.28%). The contribution of individual characteristics was mainly attributable to disparities in the enabling (26.86%) and need factors (23.86%), with the chronic conditions (15.76%), health literacy (15.56%) and average household income (15.24%) as the top three contributors. Educational level (-5.24%) was the top negative contributor, followed by commercial (-1.43%) and basic medical insurance (-0.56%). Higher inequality was found in the least developed rural (CI=0.0140) and western regions (CI=0.0134).

CONCLUSION

Pro-rich inequality in HRQoL is evident in mainland China. Targeted interventions need to prioritise measures that aim at reducing disparities in chronic conditions, health literacy and income.

Socio-demographic indicators of self-reported health based on EQ-5D-3L: A cross-country analysis of population surveys from 18 countries

Background

Generic health-related quality of life instruments, such as the EQ-5D, are increasingly used by countries to monitor population health via general population health surveys. Our aim was to demonstrate analytic options to measure socio-demographic differences in self-reported health using the EuroQol Group's archive of EQ-5D-3L population surveys that accumulated over the past two decades.

Methods

Analyses captured self-reported EQ-5D-3L data on over 100,000 individuals from 18 countries with nationally representative population surveys. Socio-demographic indicators employed were age, sex, educational level and income. Logistic regression odds ratios and the health concentration index methodology were used in the socio-demographic analysis of EQ-5D-3L data.

Results

Statistically significant socio-demographic differences existed in all countries (p < 0.01) with the EQ VAS based health concentration index varying from 0.090 to 0.157 across countries. Age had generally the largest contributing share, while educational level also had a consistent role in explaining lower levels of self-reported health. Further analysis in a subset of 7 countries with income data showed that, beyond educational level, income itself had an additional significant impact on self-reported health. Among the 5 dimensions of the EQ-5D-3L descriptive system, problems with usual activities and pain/discomfort had the largest contribution to the concentration of overall self-assessed health measured on the EQ VAS in most countries.

Conclusion

The EQ-5D-3L was shown to be a powerful multi-dimensional instrument in the analyses of socio-demographic differences in self-reported health using various analytic methods. It offered a unique insight of inequalities by health dimensions.

Quantifying changes in global health inequality: the Gini and Slope Inequality Indices applied to the Global Burden of Disease data, 1990-2017

BACKGROUND

The major shifts in the global burden of disease over the past decades are well documented, but how these shifts have affected global inequalities in health remains an underexplored topic. We applied comprehensive inequality measures to data from the Global Burden of Disease (GBD) study.

METHODS

Between-country relative inequality was measured by the population-weighted Gini Index, between-country absolute inequality was calculated using the population-weighted Slope Inequality Index (SII). Both were applied to country-level GBD data on age-standardised disability-adjusted life years.

FINDINGS

Absolute global health inequality measured by the SII fell notably between 1990 (0.68) and 2017 (0.42), mainly driven by a decrease of disease burden due to communicable, maternal, neonatal and nutritional diseases (CMNN). By contrast, relative inequality remained essentially unchanged from 0.21 to 0.19 (1990-2017), with a peak of 0.23 (2000-2008). The main driver for the increase of relative inequality 1990-2008 was the HIV epidemic in Sub-Saharan Africa. Relative inequality increased 1990-2017 within each of the three main cause groups: CMNNs; non-communicable diseases (NCDs); and injuries.

CONCLUSIONS

Despite considerable reductions in disease burden in 1990-2017 and absolute health inequality between countries, absolute and relative international health inequality remain high. The limited reduction of relative inequality has been largely due to shifts in disease burden from CMNNs and injuries to NCDs. If progress in the reduction of health inequalities is to be sustained beyond the global epidemiological transition, the fight against CMNNs and injuries must be joined by increased efforts for NCDs.

Socioeconomic status is not associated with health-related quality of life in a group of overweight middle-aged men

Socioeconomic status is a known determinant of health. In secondary data analyses, we assessed whether socioeconomic status affected health-related quality of life in a group of overweight (body mass index 25–30 kg/m²) middle-aged (45.9 ± 5.4 years) men, recruited in Auckland (New Zealand). Health-related quality of life was assessed with SF-36v2 three times: at baseline, and 12 and 30 weeks later. Socioeconomic status was determined by geo-coded deprivation scores derived from current address using the New Zealand Index of Deprivation 2006 (NZDep2006), as well as capital value of residence. Univariable and multivariable analyses showed no associations between measures of socioeconomic status and any mental or physical health domains. Our findings may reflect the fact that these men are not currently experiencing comorbidities associated with overweight.

Determinants of self-rated health and the influence of healthy behaviors: results from the National Health Survey, 2013

OBJECTIVE

To investigate the determinants of self-rated health in Brazil and the influence of healthy lifestyles.

METHODS

We used data from the National Health Survey (PNS), 2013. The self-rated health was categorized as very good/good, fair, and poor/very poor. Differences in the distribution of self-rated health according to the age group and sex were tested. Logistic regression models were used to test the effects of educational level, race/skin color, and the presence of at least one noncommunicable chronic disease on poor/very poor health perception. In addition, the influence of healthy behaviors was tested controlling for the effects of sociodemographic factors and the presence of at least one chronic disease.

RESULTS

We analyzed 60,202 individuals; about 66.1% rated their health as very good/good and 5.9% as poor/very poor; about 47.1% reported the diagnosis of at least one noncommunicable chronic disease; and only 9.3% reported a "healthy lifestyle" (do not use tobacco products, consume fruits and vegetables properly, and do physical activity during leisure time). Among the sociodemographic factors, age, sex, educational level, and race were significantly associated with self-rated health and the presence of at least one chronic disease. The effects of all healthy behaviors were statistically significant even after controlling for the other determinants.

CONCLUSION

Although the adoption of healthy lifestyles in Brazil is still insufficient, the association of healthy practices with self-perception of health found in this study is an indication that the Brazilian population is beginning to relate healthy behaviors to their well-being and better health evaluation.

Inequalities in healthy life expectancy by Federated States

OBJECTIVES

To estimate the healthy life expectancy at 60 years by sex and Federated States and to investigate geographical inequalities by socioeconomic status.

METHODS

Healthy life expectancy was estimated by the Sullivan method, based on the information of the National Survey on Health, 2013. Three criteria were adopted for the definition of “unhealthy state”: self-assessment of bad health, functionality for performing the activities of daily living, and the presence of noncommunicable disease with intense degree of limitation. The indicator of socioeconomic status was built based on the number of goods at household and educational level of the head of household. To analyze the geographical inequalities and socioeconomic level, inequality measures were calculated, such as the ratio, the difference, and the angular coefficient.

RESULTS

Healthy life expectancy among men ranged from 13.8 (Alagoas) to 20.9 (Espírito Santo) for the self-assessment criterion of bad health. Among women, the corresponding estimates were always higher and ranged from 14.9 (Maranhão) to 22.2 (São Paulo). As to the ratio of inequality by Federated State, the medians were always higher for healthy life expectancy than for life expectancy, regardless of the definition adopted for healthy state. Regarding the differences per Federated State, the healthy life expectancy was seven years higher in one state than in another. By socioeconomic status, differences of three and four years were found, approximately, between the last and first fifth, for men and women, respectively.

CONCLUSIONS

Despite the association of the mortality indicators with living conditions, the inequalities are even more pronounced when the welfare and the limitations in usual activities are considered, showing the necessity to promote actions and programs to reduce the socio-spatial gradient.

Trends in socioeconomic inequalities in self-rated health, smoking, and physical activity of Japanese adults from 2000 to 2010

Health disparities in Japan are attracting increasing attention. Temporal trends in health disparities should be continuously monitored using multiple indices of socioeconomic status (SES) and health-related outcomes. We explored changes in socioeconomic differences in the health of Japanese adults during 2000–2010. The data was taken from the Japanese General Social Surveys, the cross-sectional surveys for nationally representative samples of Japanese adults. We used 14,193 samples (individuals of 20–64 years of age) in our analysis. We estimated age-adjusted prevalence ratios of the lowest SES group in comparison with the highest SES group using Poisson regression models with robust error variance. Relative index of inequality (RII) and slope index of inequality (SII) were also calculated. We examined the changes in the association between health-related outcomes (self-rated health (SRH), smoking, and physical activity) and SES indices (income, education, occupation, and subjective social class identification). The results showed temporally expanding trends for the associations of current smoking with SES, especially among women, in both relative and absolute measures. In contrast, no expanding trends were seen for SRH and physical activity. Although the smoking rates declined through the first decade of the 21st century, the socioeconomic disparities in smoking prevalence among Japanese adults expanded, especially among women. Researchers and policymakers should continuously monitor the trends that may cause future disparities in smoking-related morbidity and mortality.

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Associations of health indicators with socioeconomic status were observed in Japan.

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We identified increasing trends in smoking disparity from 2000 to 2010 in women.

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Increasing smoking disparities were seen in both relative and absolute measures.

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Expanding trends were not seen for self-rated health and physical activity.

Socioeconomic status and self-rated health of Japanese people, based on age, cohort, and period

Background

Differences in health resulting from differences in socioeconomic status (SES) have been identified around the world. Age, period, and cohort (A-P-C) differences in health are vital factors which are associated with disparities in SES. However, few studies have examined these differences simultaneously. Moreover, although self-rated health (SRH) has been frequently used as an indicator of health, biases in reporting SRH that depend on the socioeconomic characteristics of respondents have been scarcely adjusted in the previous studies. To overcome these limitations, we investigated the associations between disparities in SES and adjusted SRH based on A-P-C, by using a repeated, cross-sectional survey of a nationally representative sample of Japanese people. In addition, we further investigated how exogenous (macroeconomic) conditions unique to a period or cohort would explain trends across successive periods and cohorts.

Methods

Data were obtained from a sample of 653,132 Japanese people that responded to the Comprehensive Survey of Living Conditions (CSLC), which is a cross-sectional survey that had been conducted every three years from 1986 to 2013, on over 10 occasions. In the CSLC, SES has been assessed by household income. We simultaneously controlled for each A-P-C dimension by using the model for cross-classification of random effects, and adjusting SRH data for reporting biases caused by differences in income and A-P-C.

Results

Differences in adjusted SRH associated with income differences decreased with age and reversed after 76 years of age. Period differences indicated that income differences peaked in 1992 and 2007. Moreover, differences in adjusted SRH associated with income differences decreased in periods with high unemployment across all periods. Furthermore, there were no cohort differences in adjusted SRH that were associated with income differences.

Conclusion

In Japan, there are age and period variations associated with adjusted differences in SRH as assessed by income. Moreover, exogenous conditions in each period could help explain periodic trends across successive periods.

Secondary Data Analysis of National Surveys in Japan Toward Improving Population Health

Secondary data analysis of national health surveys of the general population is a standard methodology for health metrics and evaluation; it is used to monitor trends in population health over time and benchmark the performance of health systems. In Japan, the government has established electronic databases of individual records from national surveys of the population’s health. However, the number of publications based on these datasets is small considering the scale and coverage of the surveys. There appear to be two major obstacles to the secondary use of Japanese national health survey data: strict data access control under the Statistics Act and an inadequate interdisciplinary research environment for resolving methodological difficulties encountered when dealing with secondary data. The usefulness of secondary analysis of survey data is evident with examples from the author’s previous studies based on vital records and the National Health and Nutrition Surveys, which showed that (i) tobacco smoking and high blood pressure are the major risk factors for adult mortality from non-communicable diseases in Japan; (ii) the decrease in mean blood pressure in Japan from the late 1980s to the early 2000s was partly attributable to the increased use of antihypertensive medication and reduced dietary salt intake; and (iii) progress in treatment coverage and control of high blood pressure is slower in Japan than in the United States and Britain. National health surveys in Japan are an invaluable asset, and findings from secondary analyses of these surveys would provide important suggestions for improving health in people around the world.

The psychometric properties of the WHOQOL-BREF in Japanese couples

This study investigated the psychometric properties of the Japanese version of the WHOQOL-BREF among 10,693 community-based married Japanese men and women (4376 couples) who were either expecting or raising a child. Analyses of item-response distributions, internal consistency, criterion validity, and discriminant validity indicated that the scale had acceptable reliability and performed well in preliminary tests of validity. Furthermore, dyadic confirmatory factor analysis revealed that the theoretical factor structure was valid and similar across partners, suggesting that men and women define and value quality of life in a similar way.

Health-related quality of life and socioeconomic status: inequalities among adults with a chronic disease

Background

A number of studies have shown an association between health-related quality of life (HRQL) and socioeconomic status (SES). Indicators of SES usually serve as potential confounders; associations between SES and HRQL are rarely discussed in their own right. Also, few studies assess the association between HRQL and SES among those with a chronic disease. The study focuses on the question of whether people with the same state of health judge their HRQL differently according to their SES, and whether a bias could be introduced by ignoring these differences.

Methods

The analyses were based on a representative sample of the adult population in Germany (n = 11,177). HRQL was assessed by the EQ-5D-3 L, i.e. the five domains (e.g. ‘moderate or severe problems’ concerning mobility) and the Visual Analog Scale (VAS). SES was primarily assessed by educational level; age, sex and family status were included as potential confounders. Six chronic diseases were selected, each having a prevalence of at least 1% (e.g. diabetes mellitus). Multivariate analyses were conducted by logistic and linear regression.

Results

Among adults with a chronic disease, most ‘moderate or severe problems’ are reported more often in the low (compared with the high) educational group. The same social differences are seen for VAS values, also in subgroups characterized by ‘moderate or severe problems’. Gender-specific analyses show that for women the associations with VAS values can just be seen in the total sample. For men, however, they are also present in subgroups defined by ‘moderate or severe problems’ or by the presence of a chronic disease; some of these differences exceed 10 points on the VAS scale.

Conclusions

Low SES groups seem to be faced with a double burden: first, increased levels of health impairments and, second, lower levels of valuated HRQL once health is impaired. These associations should be analysed and discussed in their own right, based on interdisciplinary co-operation. Social epidemiologists could include measures of HRQL in their studies more often, for example, and health economists could consider assessing whether recommendations based on HRQL scales might include a social bias.

Inequalities in self-rated health in Japan 1986-2007 according to household income and a novel occupational classification: national sampling survey series

BACKGROUND

Japan, for the past two decades, has seen economic stagnation and substantial social change. We examined whether health inequalities increased over this period.

METHODS

Using eight triennial waves of a series of large nationally representative surveys between 1986 and 2007 (n=398 303), temporal trends in relative and slope indices of inequality (RII, SII, respectively) were tested based on self-rated health in relation to theory-based social class and household income.

RESULTS

Age-standardised prevalence of self-rated fair or poor health showed V-shaped time trends in both sexes with the lowest prevalence in early/mid-1990s. In 1986, RII and SII in household social class and income were significant for both sexes. In men, RII and SII according to income showed significant narrowing of temporal trends in poor health (-1.4% and -0.1% annually, respectively), but these were stable in women. After multilevel multiple imputation for missing income data, the findings in men were not altered but narrowing trends became evident and significant in women (-1% and -0.1% annually, respectively). Inequality indices for social class remained constant over the study period in both sexes.

CONCLUSIONS

Relative and absolute health inequalities for social class and income based on self-rated fair or poor health narrowed or remained stable between 1986 and 2007, despite the economic stagnation and adverse social changes. Overall population health across socioeconomic groups initially improved but then worsened. The positive finding regarding the health inequality trend seen in the Japanese context is informative for the wider international community during this period of economic uncertainty.

Opposite poles: A comparison between two Spanish regions in health-related quality of life, with implications for health policy

BACKGROUND

Although health is one of the main determinants of the welfare of societies, few studies have evaluated health related quality of life in representative samples of the population of a region or a country. Our aim is to describe the health-related quality of life of the inhabitants of two quite different Spanish regions (Canary Islands and Catalonia) and to compare the prevalence of health problems between age-sex groups.

METHODS

We use data obtained from the 2006 Health Survey of Catalonia and the 2004 Canary Islands Health Survey. With an ordinal composite variable measuring HRQOL we identify the association of characteristics of individuals with self-reported quality of life and test for differences between the regions.

RESULTS

The prevalence of problems in the five EQ-5 D dimensions increases with age and is generally higher for women than for men. The dimension with the highest prevalence of problems is "anxiety/depression", and there is noteworthy the extent of discomfort and pain among Canary Island women. Education, especially among the elderly, has an important effect on health-related quality of life.

CONCLUSIONS

There are substantial structural and compositional differences between the two regions. Regional context is a significant factor, independent of the compositional differences, and the effects of context are manifest above all in women. The findings show the importance of disease prevention and the need for improving the educational level of the population in order to reduce health inequalities.

[Health-related quality of life of working-age immigrant population]

INTRODUCTION

The intense wave of immigration to Spain since the mid-1990s has posed a major challenge to the organization of the Spanish health system. Consequently, knowledge of the health status of the new immigrant population is highly important. The aim of this study is to analyze health-related quality of life in the working-age (16-50 years) immigrant population.

METHODS

We use data from the 2006 Catalan Health Survey and probit models to analyze each of the five dimensions of the EQ-5D, a generic health-related quality of life measure (dependent variables). As explanatory variables we use: (i) socio-demographic characteristics, (ii) health (diagnosed illnesses, accidents), and (iii) lifestyles. Immigrant status is included as an explanatory variable, and alternative probit models were used to analyze each of the dimensions of the quality of life instrument.

RESULTS

Immigrant status is significantly associated with lower health status in the dimensions of pain/discomfort and anxiety/depression. Our results show that the differences between the immigrant and native-born population vary between men and women, and also depend on country of birth and length of residence in Spain.

DISCUSSION

The results show that the working-age immigrant population has lower health-related quality of life. These results add a rider in the healthy immigrant effect hypothesis. However, there is substantial heterogeneity within the immigrant collective and thus other variables, such as country of birth and time since arrival in Spain, should be taken into account before reaching any final conclusions.

A tale of two countries--the United States and Japan: are differences in health due to differences in overweight?

Background

Despite similar standards of living and health care systems for older persons, there are marked differences in the relative health of the elderly populations in the United States (US) and Japan. We explore the association of overweight and obesity with these health disparities.

Methods

Data on older adults from the US National Health Interview Survey (1994) and the Longitudinal Study of Aging II (1994) were compared to similar data from the 1999-2001 Nihon University Japanese Longitudinal Study of Aging. Regression analyses for the 2 countries were conducted to examine the correlates of being overweight and obese, and the relationships of overweight and obesity with activities of daily living functioning, heart disease, arthritis, and diabetes.

Results

The prevalence of overweight and obesity is higher in the US than in Japan, as is the prevalence of heart disease, diabetes, arthritis, and functioning problems. Education level and marital status are predictors of overweight for older Americans but not for older Japanese people. Health behaviors affect weight in all groups. The prevalence of functioning problems and disease are more likely to be associated with being overweight in US men and women than in Japanese women, and are not associated with being overweight in Japanese men.

Conclusion

Despite similar standards of living and health care systems for older persons, the conditions associated with poor health differ in the US and Japan. Being overweight or obese appears to be related to more functioning problems and arthritis in the US than in Japan.

US norms for six generic health-related quality-of-life indexes from the National Health Measurement study

BACKGROUND

A number of indexes measuring self-reported generic health-related quality-of-life (HRQoL) using preference-weighted scoring are used widely in population surveys and clinical studies in the United States.

OBJECTIVE

To obtain age-by-gender norms for older adults on 6 generic HRQoL indexes in a cross-sectional US population survey and compare age-related trends in HRQoL.

METHODS

The EuroQol EQ-5D, Health Utilities Index Mark 2, Health Utilities Index Mark 3, SF-36v2 (used to compute SF-6D), Quality of Well-being Scale self-administered form, and Health and Activities Limitations index were administered via telephone interview to each respondent in a national survey sample of 3844 noninstitutionalized adults age 35-89. Persons age 65-89 and telephone exchanges with high percentages of African Americans were oversampled. Age-by-gender means were computed using sampling and poststratification weights to adjust results to the US adult population.

RESULTS

The 6 indexes exhibit similar patterns of age-related HRQoL by gender; however, means differ significantly across indexes. Females report slightly lower HRQoL than do males across all age groups. HRQoL seems somewhat higher for persons age 65-74 compared with people in the next younger age decade, as measured by all indexes.

CONCLUSIONS

Six HRQoL measures show similar but not identical trends in population norms for older US adults. Results reported here provide reference values for 6 self-reported HRQoL indexes.

Different income information as an indicator for health inequality among Japanese adults

BACKGROUND

There are several alternative indicators of income information, which is a fundamental measure of individual socioeconomic position. In this study, we compared the degrees of associations of four types of income information with health variables among Japanese adults.

METHODS

Using a nationally representative sample of 29,446 men and 32,917 women aged 20 years and over, the associations between four income indicators and health variables were examined using the odds ratio in logistic regression analysis and the concentration index by sex and age group (20-59 years and 60+ years). Income indicators consisted of total household income, equivalent household income, total household expenditure, and equivalent household expenditure. Current smoking and self-rated health statuses were used as health variables.

RESULTS

A low income was associated with a high prevalence of smoking and fair/poor self-rated health, with some differences among sex and age groups and income indicators, but less difference among methods of statistical analyses. Total and equivalent incomes were similarly and more markedly associated with smoking and self-rated health statuses, whereas equivalent expenditure showed the smallest degree of health difference. For the population aged 60+ years, the degree of health differences in smoking was similar between income and expenditure.

CONCLUSIONS

Although the degree of income-related health differences is dependent on health outcome and both sex and age group, this study suggests that either crude or equivalent household income is a useful indicator for health inequality among Japanese adults.

Is Health Inequality Across Individuals of Moral Concern?

The history of the documentation of health inequality is long. The way in which health inequality has customarily been documented is by comparing differences in the average health across groups, for example, by sex or gender, income, education, occupation, or geographic region. In the controversial World Health Report 2000, researchers at the World Health Organization criticized this traditional practice and proposed to measure health inequality across individuals irrespective of individuals' group affiliation. They defended its proposal on the moral grounds without clear explanation. In this paper I ask: is health inequality across individuals of moral concern, and, if so, why? Clarification of these questions is crucial for meaningful interpretation of health inequality measured across individuals. Only if there was something morally problematic in health inequality across individuals, its reduction would be good news. Specifically, in this paper I provide three arguments for the moral significance of health inequality across individuals: (a) health is special, (b) health equity plays an important and unique role in the general pursuit of justice, and (c) health inequality is an indicator of general injustice in society. I then discuss three key questions to examine the validity of these arguments: (i) how special is health?, (ii) how good is health as an indicator?, and (iii) what do we mean by injustice? I conclude that health inequality across individuals is of moral interest with the arguments (b) and (c).

Assessment of the health of Americans: the average health-related quality of life and its inequality across individuals and groups

BACKGROUND

The assessment of population health has traditionally relied on the population's average health measured by mortality related indicators. Researchers have increasingly recognized the importance of including information on health inequality and health-related quality of life (HRQL) in the assessment of population health. The objective of this study is to assess the health of Americans in the 1990s by describing the average HRQL and its inequality across individuals and groups.

METHODS

This study uses the 1990 and 1995 National Health Interview Survey from the United States. The measure of HRQL is the Health and Activity Limitation Index (HALex). The measure of health inequality across individuals is the Gini coefficient. This study provides confidence intervals (CI) for the Gini coefficient by a bootstrap method. To describe health inequality by group, this study decomposes the overall Gini coefficient into the between-group, within-group, and overlap Gini coefficient using race (White, Black, and other) as an example. This study looks at how much contribution the overlap Gini coefficient makes to the overall Gini coefficient, in addition to the absolute mean differences between groups.

RESULTS

The average HALex was the same in 1990 (0.87, 95% CI: 0.87, 0.88) and 1995 (0.87, 95% CI: 0.86, 0.87). The Gini coefficient for the HALex distribution across individuals was greater in 1995 (0.097, 95% CI: 0.096, 0.099) than 1990 (0.092, 95% CI: 0.091, 0.094). Differences in the average HALex between all racial groups were the same in 1995 as 1990. The contribution of the overlap to the overall Gini coefficient was greater in 1995 than in 1990 by 2.4%. In both years, inequality between racial groups accounted only for 4-5% of overall inequality.

CONCLUSION

The average HRQL of Americans was the same in 1990 and 1995, but inequality in HRQL across individuals was greater in 1995 than 1990. Inequality in HRQL by race was smaller in 1995 than 1990 because race had smaller effect on the way health was distributed in 1995 than 1990. Analysis of the average HRQL and its inequality provides information on the health of a population invisible in the traditional analysis of population health.