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A comparison of socioeconomic differences in physical functioning and perceived health among male and female employees in Britain, Finland and Japan
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Social Science & Medicine 59 (2004) 1287–1295
A comparison of socioeconomic differences in physical functioning and perceived health among male and female employees in Britain, Finland and Japan Pekka Martikainena,b,*, Eero Lahelmac, Michael Marmotb, Michikazu Sekined, Nobuo Nishie, Sadanobu Kagamimorid a
Department of Sociology, Population Research Unit, P. O. Box 18, University of Helsinki, FIN-00014, Finland b Department of Epidemiology and Public Health, International Centre for Health and Society, University College London Medical School, 1-19 Torrington Place, London WC1E 6BT, UK c Department of Public Health, P. O. Box 41, University of Helsinki, FIN-00014, Finland d Department of Welfare Promotion and Epidemiology, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan e Department of Hygiene and Preventive Medicine, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
Abstract We compared the pattern of socioeconomic inequalities in physical functioning and perceived health among male and female employees in Britain, Finland and Japan. Participants were male and female public sector employees in Britain, Finland and Japan, who were economically active and 40–60 year-olds at the time of data collection. We measured perceived health and physical functioning (SF-36 physical component summary) with standardized health questionnaires. The results obtained here reconfirm the similarity of the patterns of ill-health of those with lower socioeconomic status among non-manual men and women in Britain and Finland. These data also provide good evidence for a socioeconomic gradient in ill-health among Japanese non-manual men, although this gradient was less systematic. For Japanese men poorer health of manual workers as compared to non-manual workers was well demonstrated. However, among Japanese women socioeconomic differences in health were small and inconsistent. In conclusion, Britain, Finland and Japan—representing ‘liberal’, ‘Nordic’ and ‘conservative’ welfare state regimes— produce broadly similar patterns of socioeconomic differences in health among men. However, different patterns of labour force participation and welfare provision in different welfare regimes may bring about different patterns of socioeconomic differences in health for working women. This is exemplified by the lack of health inequalities among employed Japanese women. r 2004 Elsevier Ltd. All rights reserved.
Introduction In industrialized western European and north American countries health follows a hierarchical pattern: the *Corresponding author. Department of Sociology, Population Research Unit, P. O. Box 18, University of Helsinki, FIN00014, Finland. Tel.: +358-9-191-23889; fax: +358-9-19123967. E-mail address: pekka.martikainen@helsinki.fi (P. Martikainen).
lower the socioeconomic status, the poorer the health. European comparisons show that the magnitude of socioeconomic inequalities in ill-health and mortality vary among countries (Mackenbach, Kunst, Cavelaars, Groenhof, & Geurts, 1997a; Cavelaars et al., 1998; Kunst, Groenhof, Mackenbach, & Health, 1998; Lahelma et al., 2002). Furthermore, even when similar levels of inequalities in total mortality are observed, very different specific causes may be responsible; alcohol associated causes and cardiovascular diseases being important contributors to overall inequalities (Kunst et al., 1998).
0277-9536/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.socscimed.2004.01.005
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These results highlight the importance of comparative studies in identifying the common and unique determinants of socioeconomic inequalities in health. Comparative studies help us to identify countries or settings with particularly large or small inequalities in health. Such studies can provide a possibility to try to identify the circumstances that are associated with inequalities in health. Small inequalities may, for example, be related to small inequalities in material conditions of life, favourable working conditions and equitable distribution of welfare services. These in turn limit the behavioural choices that individuals can make in terms of smoking, use of alcohol, exercise and intake of fruit and vegetables (Laaksonen, Pr.att.al.a, Helasoja, Uutela, & Lahelma, 2003). Comparing countries may sometimes be the only feasible way to evaluate how policy affects health inequalities, and thus help us to distinguish which among a multitude of factors has the greatest potential to reduce health differences. Simultaneously comparative studies improve our understanding of the limits and generalisability of explanations of inequalities in health obtained in particular national settings. Relatively little comparative research on socioeconomic inequalities in health that include countries of non-European heritage are available. However, analyses of Japan indicate that socioeconomic inequalities in mortality, ill-health and risk factors exist, but the magnitude and pattern of these inequalities are not as consistent as in western countries (Kagamimori, Iibuchi, & Fox, 1983; Kagamimori et al., 1998; Netherlands Central Bureau of Statistics, 1992; Kawakami, Haratani, Hemmi, & Araki, 1992). For example, an earlier comparison of socioeconomic inequalities in risk factors among British and Japanese employed men showed, that although a ‘western inequality pattern’ was observed for some risk factors, it could not be observed for weight (BMI), waist-to-hip-ratio and HDL cholesterol (Martikainen, Ishizaki, Marmot, Nakagawa, & Kagamimori, 2001). Thus, caution is needed against uncritical extrapolation of results on health inequalities from western countries to non-western countries, such as Japan. The aim of this study is to compare the patterns of socioeconomic inequalities in physical functioning and perceived health among male and female government employees in Britain, Finland and Japan. These three countries represent the ‘liberal’, the ‘Nordic’ or ‘social democratic’ and the ‘conservative’ welfare regimes, respectively, each characterised by a different pattern of welfare production and allocation (Esping-Andersen, 1990, 1999). Previous evidence of health inequalities being associated with welfare regimes is inconclusive (Mackenbach et al., 1997a). ‘A welfare regime can be defined as the combined, interdependent way in which welfare is produced and allocated between state, market and family’ (Esping-Andersen, 1999, p. 35). Under this
broad definition of a welfare regimes there are at least three factors that may be put forward as having a significant contribution for socioeconomic differences in health. These relate to the following: (1) differences in the direct material consequences of redistributive income policies and universalistic and egalitarian principles in the provision of social benefits, education and health care; (2) differences in the psychosocial and psychological consequences of these policies in terms of sense of belonging, feelings of cohesion and sense of security; and (3) differences in the working of the labour market in terms of gender segregation, the male ‘bread-winner’ model and the ability of women to participate in paid work.
Data and methods Participants Participants of the Japanese, Finnish and British cohorts were recruited from municipal, provincial and national public sector work places. Because socioeconomic differences in ill-health in Japan are poorly documented, we use data for two different Japanese cohorts. Those invited to participate were sent a standardised self-report health questionnaire. In Japan questionnaires were sent to the employees of a prefecture on the west coast of Japan (Kagamimori, Sekine, Nasermoaddeli, & Hamanisi, 2002), and Takarazuka City (Nishi, Makino, Fukuda, & Tatara, 2003) in 1998–1999 and 1997–1998, respectively. All employees were invited to participate. The response rates were 88% and 83% correspondingly. The Finnish data derived from the Helsinki Health Study baseline survey of municipal employees from the City of Helsinki in 2000 and 2001 (Kivel.a et al., 2001) and aged 40, 45, 50, 55 or 60 at the time of the survey in each year. The response rate was 68%. The British cohort comprised of employees working in the London offices of twenty National Government Civil Service departments and recruited in 1985–1988 (the Whitehall II study) (Marmot et al., 1991). The overall response rate was 73%, although the true response rate is likely to be higher because around 4% of those listed as employees were not eligible as they had moved before the study. For this study we included men and women who participated in the baseline of the Japanese and Finnish studies or in the third phase of the British study (1991– 1993) and were economically active and 40–60 year-olds at that time. Altogether 2255 participants from the prefecture on the west coast of Japan, 1060 from Takarazuka, 5886 from Helsinki, and 6942 from London were included. The cross-sectional nature of these data limit strong causal interpretations of the
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results. Generalisations of our results to national populations should be carried out with caution. Measurement of socioeconomic status In all cohorts information on employment grade—our measure of socioeconomic status—was obtained, and the following hierarchical grades were used: (1) managerial/administrative, (2) professional and semi-professional, (3) clerical employees, and (4) manual workers. In the cohort on the west coast of Japan employment grade was based on the questionnaire of the Japanese national survey for occupations that distinguishes between 13 broad occupational categories. These were allocated into the four grades and were made up of the following specific occupations: (1) managerial grade consisted of provincial government officials in senior positions, such as legislators, governors, accounting officials, directors and heads of division, and heads of section, (2) professional grade consisted mainly of engineers and health care employees, e.g. mechanical, electrical, computer, civil and surveying engineers, physicians, dentists, veterinarians, pharmacists, nurses, midwives and nutritionists, but also judges, social workers, welfare advisers and teachers, (3) general office staff, e.g. clerical workers and accounting clerks, and (4) manual workers were mainly bus, truck and ambulance drivers. In the Takarazuka cohort employment grade was based on questionnaire information on job rank and type of occupation used within the city administration and was classified in the following way: (1) managerial employees at the department director and section chief levels, (2) professionals, e.g. doctors, nurses, teachers and technicians, (3) office based clerical employees below the section chief level, and (4) manual workers, e.g. school janitors, canteen workers, drivers and fire fighters. In the Helsinki cohort employment grade was based on combined information from the personnel register data of the City of Helsinki and questionnaire data. The classification schema was based on hierarchical employment grade levels used in City of Helsinki for office employees, and manual workers were distinguished using the Statistics Finland (Statistics Finland, 1989) classification in the following way: (1) managers in supervisory positions, (2) professionals (e.g. doctors, teachers and social workers) and semi-professionals (e.g. nurses among women, and foremen and technicians among men), (3) clerical employees and other female dominated non-professional occupations within the social and health care (e.g. child minders, assistant nurses and secretaries), and (4) manual workers (e.g. bus drivers, janitors, fire fighters, cleaners and canteen workers). On the basis of questionnaire information three grades were obtained in London based cohort of civil servants by collapsing the 12 non-industrial salary based
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grade levels used in the Civil Service in the following way: (1) managerial grade consisted of unified grades 1– 6 (Permanent Secretary to Senior Principal), (2) professional and executive group was made up of unified grade 7 (Principal), senior executive officers, higher executive officers and executive officers, and (3) clerical grade consisted of clerical officers and clerical assistants. There were no manual workers within the British national government civil service. With these data employment grade classifications among non-manual employees could not be obtained using strictly harmonised instruments. Nevertheless, the employment grade variables that we have used here are strictly hierarchical in all cohorts. The data do not enable us to draw conclusions on the exact magnitude of employment grade differences in health, but are reliable for analyses of the broad hierarchical patterns of socioeconomic health inequalities. Measurement of health outcomes Physical health functioning was measured with the SF-36 questionnaire which covers issues relating to physical, psychological and social functioning and is coded into eight scales: physical functioning, role limitations due to physical problems, social functioning, bodily pain, general mental health, role limitations due to emotional problems, vitality, and general health perceptions. These eight scales are summarised into physical and mental functioning component summaries by a method based on factor analysis (Ware, Kosinski, & Keller, 1994; Ware et al., 1995). For all cohorts we used US general population weights to calculate physical component summaries. Low scores imply low physical functioning and a mean of 50 is observed in the US general population (Ware et al., 1995). For Finland and Japan we used SF-36 translations (Hagman, 1996; Fukuhara, Bito, Green, Hsiao, & Kurokawa, 1998a; Fukuhara, Ware, Kosinski, Wada, & Gandek, 1998b). In the Whitehall II study the correlation between physical component and the physical functioning score was 0.75, and the correlation between the physical and mental components was 0.04. For Helsinki these correlations were 0.81 and 0.03 and for both of the Japanese cohorts 0.67 and 0.10, respectively. In all cohorts physical health functioning was strongly associated with longstanding illness and history of heart disease (angina, heart attack, hypertension; results from the author). For these analyses poor physical health functioning was defined as having a score below the 25th percentile. The percentile cutpoint was obtained from data that pool the four study cohorts. Perceived general health was obtained from a question with equal wording in each cohort: ‘In general would you say your health is’ with five response alternatives ranging from ‘excellent’ to ‘poor’. Perceived
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health reflects a broad range of medical and other health status information available to the individual ranging from knowledge of existing diseases through cognitive and affective characteristics of individuals and personality (Manderbacka, 1998). The measure is regarded as suitable for comparative purposes, because it is simple to ask and has produced consistent results in different countries (de Bruin, Pichavet, & Nossikov, 1996; Idler & Benyamini, 1997; Jylh.a, Guralnik, Ferrucci, & Jokela, 1998). For these analyses the outcome was categorised as 0=good, very good and excellent and 1=fair and poor. Statistical methods The association between employment grade and our two measures of health were analysed using logistic regression in STATA statistical package (Stata Reference Manual, 1992). We enter employment grade as a categorical explanatory variable to the models; four categories for the Finnish and Japanese cohorts and three categories for the British cohort. We adjusted for categorical age in single years. Among men the highest grade (administrative/managerial) was used as the reference category. However, among women we used the second highest employment grade (professional) as the reference, because the highest grade had only very few observations in the Japanese cohorts. The results are presented in terms of odds ratios together with 95% confidence intervals. Analyses were conducted separately in men and women and for each cohort. As a summary index—here referred to as the inequality index—for the employment grade differences in health among non-manual workers we estimated a continuous logistic regression coefficient for employment grade with each category being assigned values 1– 3. This method gives a more stable effect estimate since data for all employment grades are used. It has an intuitive interpretation as the increase in ill-health for each step down the employment grade ladder, e.g. a value of the index of 1.50 obtained from logistic regression analyses indicates that ill-health increases by a factor of 1.50 (expressed in terms of the odds ratio) from one grade to the next (Mackenbach & Kunst, 1997b). The index imposes linearity on the association between employment grade and health. Departures from linearity can be assessed from Tables 2 and 3. The index is a measure of total effect, as it takes into account both the strength of the health differences between groups as well as the distribution of the population into these groups.
In particular, very few Japanese women occupy higher grades. These differences are partly due to the higher socioeconomic composition of the British civil servants recruited from London based national government departments, and differences in the occupational structure between city and provincial employees. Among men and women differences in the prevalence of fair or poor perceived health and poor physical functioning were observed, with British civil servants having better health than the other cohorts. Partly these differences reflect differences in the socioeconomic composition of these cohorts mentioned above, but partly they may also reflect true differences in health status, or cultural differences in health reporting. Among non-manual male employees a consistent employment grade gradient in fair or poor perceived health (Table 2) was observed in all the four cohorts. Odds ratio for perceived health in the clerical grade as compared to the administrative/managerial grade varied between 1.61 (95% CI 0.97–2.70) in Helsinki to 3.20 (95% CI 2.31–4.43) in London. In the analyses of women we have used the professional grade as the reference group, because of the bottom heavy distribution of women, particularly in Japan. Among Japanese non-manual women negligible grade differences in fair or poor perceived health were observed, while in Helsinki and London lower grade women had consistently worse perceived health. For poor physical functioning (Table 3) a typical western pattern of health inequalities again emerged among non-manual Finnish and British men. However, in the two Japanese cohorts these differences were smaller and less systematic. Among Japanese women the differences between non-manual grades were inconsistent; i.e. the grade gradients were in the opposite directions in the two cohorts. Poorer physical functioning in the lower non-manual grades were observed in the Helsinki and the London cohorts among women. In the Helsinki and both Japanese cohorts a manual grade could also be identified. In all these cohorts manual men had poorer perceived health and poorer physical functioning than all non-manual men, with the exception of manual men in the cohort on the west coast of Japan whose perceived health was similar to that of the professional employees. The poorer health of Japanese manual women was less clear.
Discussion Socioeconomic differences among men
Results Proportionally more British employees work in the top grade than Japanese and Finnish employees (Table 1).
For men earlier studies comparing socioeconomic inequalities based on occupational social position in Britain and Finland suggest that the pattern and magnitude of health inequalities in these two countries
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Table 1 Mean age, prevalence of poor physical functioning, prevalence of fair or poor perceived health, and distribution (%) of study participants by employment grade West coast of Japan Men Mean age Prevalence of poor physical functioning Prevalence of fair or poor perceived health Employment grade Non-manual Administrative/managerial Professional Clerical Manual All N Women Mean age Prevalence of poor physical functioning Prevalence of fair or poor perceived health Employment grade Non-manual Administrative/managerial Professional Clerical Manual All N
Takarazuka
Helsinki
London
49.2 24.6 27.6
48.6 24.2 37.3
49.9 25.7 28.8
48.5 13.2 9.3
12.8 45.3 30.5 11.4 100.0 1800
9.3 20.8 29.6 30.4 100.0 794
16.5 45.8 10.7 27.1 100.0 1182
47.7 45.6 6.7 — 100.0 4802
48.5 37.4 35.1
48.5 39.5 40.3
49.1 33.3 26.8
49.7 27.7 14.1
1.1 61.7 30.4 6.8 100.0 708
1.1 21.1 40.9 36.8 100.0 266
7.9 38.2 43.1 10.8 100.0 4704
15.9 45.0 39.1 — 100.0 2140
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. Table 2 Age-adjusted odds ratios of fair or poor perceived health by employment grade
Men N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades Women N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades
West coast of Japan
Takarazuka
Helsinki
London
OR
OR
OR
OR
95% CI
1796 1.00 1.63 2.56 1.57 1.56
821
1.10–2.42 1.68–3.89 0.97–2.53 1.30–1.89
706 0.59 1.00 1.04 0.74 1.08
95% CI
1.00 1.83 2.26 2.28 1.42
1210
1.11–3.04 1.40–3.65 1.43–3.63 1.12–1.80
287 0.11–3.14 0.73–1.48 0.38–1.45 0.77–1.51
—a 1.00 1.01 2.15 1.28
95% CI
1.00 1.17 1.61 2.41 1.27
4807
0.79–1.72 0.97–2.70 1.60–3.63 0.98–1.65
4852 — 0.51–2.01 1.05–4.38 0.65–2.54
0.96 1.00 1.50 2.20 1.35
95% CI
1.00 1.49 3.20 — 1.69
1.20–1.84 2.31–4.43 — 1.45–1.97
2150 0.73–1.26 1.29–1.75 1.78–2.72 1.21–1.51
0.69 1.00 1.65 — 1.58
0.45–1.05 1.26–2.16 — 1.31–1.92
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. a Odds ratio is not estimated as it would be based on three observations.
is broadly similar for perceived health, but inequalities are perhaps somewhat larger in Finland for limiting long-standing illness (Lahelma, Arber, Rahkonen, &
Silventoinen, 2000). However, differences in perceived health by household income were possibly a little larger in Britain (Rahkonen, Arber, Lahelma, Martikainen, &
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Table 3 Age-adjusted odds ratios of poor physical functioning by employment grade
Men N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades Women N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades
West coast of Japan
Takarazuka
Helsinki
London
OR
OR
OR
OR
95% CI
1800
95% CI
794
95% CI
1182
95% CI
4802
1.00 1.40 1.47 1.56
0.96–2.06 0.97–2.22 0.98–2.48
1.00 1.15 1.05 1.99
0.65–2.04 0.60–1.82 1.19–3.32
1.00 1.58 1.83 2.83
1.04–2.40 1.05–3.20 1.82–4.41
1.00 1.27 1.96 —
1.06–1.51 1.45–2.65 —
1.15
0.95–1.40
0.95
0.72–1.26
1.38
1.05–1.81
1.35
1.18–1.54
708 0.39 1.00 0.68 0.93 0.75
266 0.07–2.10 0.47–0.98 0.49–1.77 0.53–1.05
—a 1.00 1.80 2.63 2.46
4704 — 0.84–3.86 1.17–5.91 1.14–5.29
1.03 1.00 1.58 2.10 1.38
2140 0.80–1.33 1.38–1.82 1.71–2.59 1.24–1.53
0.67 1.00 1.25 — 1.33
0.49–0.91 1.01–1.54 — 1.15–1.54
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. a Odds ratio is not estimated as it would be based on three observations.
Silventoinen, 2000). Overall both countries have socioeconomic inequalities in health that are of average European level (Cavelaars et al., 1998; Mackenbach et al., 1997a). Some evidence indicates that mortality differences may be larger in Finland than in the UK (Mackenbach et al., 1997a). The results obtained here reconfirm the broad similarity of occupation based socioeconomic (employment grade) gradients in health among non-manual men in these two countries. Among Japanese men, a tendency for lower grade non-manual employees to have poorer health was also observed, although this was somewhat less consistent for physical functioning. An earlier comparison of socioeconomic inequalities in risk factors among British and Japanese employed men is consistent with this by showing that a western inequality pattern was observed for many, but not necessarily all risk factors among Japanese employees (Martikainen et al., 2001). Furthermore, these data show that manual male workers in Japan have poorer health than non-manual male workers. This is consistent with poorer physical functioning and perceived health of Finnish male manual workers observed in this study, and evidence elsewhere (Lahelma et al., 2000; Mackenbach et al., 1997a). Socioeconomic differences among women For women the two European cohorts differed markedly from the Japanese cohorts. Clear employment grade differences were observed for Finnish and British
non-manual employees. While among Japanese women socioeconomic differences in health were small and inconsistent. It is worth pointing out that comparative studies of socioeconomic inequalities of women’s health are rare and have mainly used standard survey data (e.g. from national level of living surveys) on national populations of working and non-working women. In addition, because of problems in allocating non-working women into occupation based socioeconomic categories these studies have typically focussed on other measures of socioeconomic status, such as education (Cavelaars et al., 1998; Lahelma et al., 2002). The three countries that we have studied represent three different welfare regimes as proposed by EspingAndersen. Britain, Finland and Japan belong to the ‘liberal’, the ‘Nordic’ or ‘social democratic’ and the ‘conservative’ welfare regimes, respectively (EspingAndersen, 1990, 1999). There are several characteristics of welfare regimes that may have significance for socioeconomic differences in employed women’s health, particularly in Japan. In Japan inconsistent or small socioeconomic differences in health were observed. For physical functioning the two cohorts showed inequalities in opposite directions and for perceived health the differences were nonexistent. Also the level of health among manual workers was inconsistent among Japanese women. The Japanese ‘conservative’ welfare regime is characterised by low female attachment to paid work. Female labour force
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participation is low and part-time work is common (Iwai, Fujioka, Yoshinaga, & Sugihashi, 2002; OECD). Furthermore, the status of the jobs that women occupy are disproportionately at the bottom of the occupational hierarchy (Iwai et al., 2002). For example, in these data about 1% of women were in administrative or managerial jobs. Accordingly, wage differences between men and women are large, and there is a strong dependence on family responsibility in welfare provision geared around the well-earning male ‘bread-winner’ (EspingAndersen, 1999; Jacobs, 1998). Thus, the paid jobs women hold are likely to have lesser importance on their general welfare and material quality of life and are accordingly of lesser importance in driving socioeconomic inequalities in health. The results suggest that analyses of socioeconomic inequalities in women’s health in Japan and possibly in ‘conservative’ welfare regime countries more generally may be better carried out using household based measures of socioeconomic status, such as household income or the socioeconomic status of the person in the household with the highest status. Occupation based socioeconomic differences in perceived health and physical functioning among British and Finnish female non-manual employees were quite similar in this study. To some extent this finding was unexpected, because contrary to our results, previous findings on the working and as well as non-working female populations categorized according to the women’s own current or previous occupation based social position indicate that differences in perceived health and limiting long-standing illness in Finland are somewhat larger than in Britain (Lahelma et al., 2000). The larger occupation based socioeconomic differences in health among Finnish women can be explained in terms of female labour market characteristics. The Nordic social democratic welfare regime, particularly Finland, is characterised by exceptionally high full-time labour force participation, and universal social benefits (e.g. daycare and parental leave arrangements) that enable women to combine motherhood and paid employment. In Britain publicly funded daycare facilities are modest and female labour force participation is much lower than in Finland. Accordingly, this stronger attachment of Finnish women to the labour market may be associated with greater discriminatory power of women’s own socioeconomic position in Finland than in Britain. Our finding of quite similar socioeconomic differences in health in the two cohorts may be partly due to the closer comparability of our public sector cohorts than two samples of national populations in terms of, e.g. working conditions and occupational distributions. However, a study using education as a measure of socioeconomic status in 11 countries (Cavelaars et al., 1998) found great similarity in differences in perceived
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health, and another study on household income indicated somewhat larger inequalities in Britain (Rahkonen et al., 2000). Thus, no clear overall picture on the relative strength of socioeconomic inequalities in women’s health in Britain and Finland emerges. Methodological considerations International comparisons of socioeconomic differences in health may be affected by data comparability problems. The strength of our data is that information on health outcomes was collected with identical instruments in all cohorts. Furthermore, all cohorts consisted of public sector employees, and thus form more homogeneous and comparable populations. A potential weakness of these data is that within non-manual employees employment grade classifications could not be obtained using strictly harmonised instruments. Nevertheless, the employment grade structure that we have used here is strictly hierarchical in all cohorts, and although caution is needed in drawing conclusions on the exact magnitude of employment grade differences in health, our findings are reliable in assessing the broad patterns of socioeconomic health inequalities. Further comparative studies using different indicators of socioeconomic position—such as education and household based indicators—are needed. Furthermore, these results are compatible with previous comparative work on men showing that risk factors for major diseases are less consistently associated with socioeconomic hierarchy in Japan than in western Europe (Martikainen et al., 2001). In addition, direct generalisations of these findings to the respective national populations should be carried out cautiously. All cohorts consist of employed men and women, a healthy sub-set of the general population (Martikainen & Valkonen, 1999), and are recruited from regions that may not be representative of the respective countries more generally.
Conclusion Our results emphasize the importance of comparative studies of socioeconomic inequalities in health among men and women in different national settings. We have shown that socioeconomic differences in ill-health vary between Japanese, Finnish and British employees, and that particularly Japanese women show little evidence of the western pattern of inequality in health so far. Britain, Finland and Japan—representing ‘liberal’, ‘Nordic’ and ‘conservative’ welfare state regimes— produce broadly similar patterns of socioeconomic differences in health among men. However, different patterns of labour force participation and welfare provision in different welfare regimes may be associated
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with different patterns of socioeconomic differences in health for employed women. We could find no evidence that inequalities in health are smaller in a cohort from the ‘Nordic’ welfare regime (see also Mackenbach et al., 1997a). The results indicate that different social structural contexts and historical settings shape the pattern of socioeconomic inequalities in health.
Acknowledgements This work is part of the European Science Foundation program on Social Variations in Health Expectancy in Europe, in particular the working group on Macrosocial Determinants of Morbidity and Mortality. The Helsinki Health Study is supported by grants from the Academy of Finland, Research Council for Health (48119, 48553 and 53245) and the Finnish Work Environment Fund (99090). The Whitehall II study has been supported by grants from the Medical Research Council, British Heart Foundation, Health and Safety Executive, National Heart Lung and Blood Institute (HL36310), National Institute on Aging (AG13196), Agency for Health Care Policy Research (HS06516), The New England Medical Centre: Division of Health Improvement, Institute for Work and Health, Toronto, and the John D and Catherine T MacArthur Foundation Research Networks on Successful Midlife Development and Socioeconomic Status and Health. PM has a fellowship and a grant (70631, 48600) from the Academy of Finland. MM is supported by a United Kingdom MRC Research Professorship. We wish to thank participating employees, and the research teams in all collaborating centers. Elina Nihtil.a and Peppiina Saastamoinen helped in carrying out the analyses and preparing the tables.
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Netherlands Central Bureau of Statistics and Erasmus University Department of Public Health and Social Medicine (compiled by Kunst AE, Geurts JGG, Berg J van den). (1992). International variation in socio-economic inequalities in self-reported health. A comparison of the Netherlands with other industrialised countries. Netherlands Central Bureau of Statistics, Voorburg/Heerlen. Nishi, N., Makino, K., Fukuda, H., & Tatara, K. (2003). Effects of socioeconomic indicators on coronary risk factors, self-rated health and psychological well-being among urban Japanese civil servants. Social Science & Medicine, forthcoming. OECD. Labour Market Statistics—Indicators. http://www. oecd.org. Rahkonen, O., Arber, S., Lahelma, E., Martikainen, P., & Silventoinen, K. (2000). Understanding income inequalities in health among men and women in Britain and Finland. International Journal of Health Services, 30, 27–47. Stata Reference Manual: Release 3 (5th ed.) (1992). Santa Monica, CA: Computing Resource Center. Statistics Finland. (1989). Socio-economic classification. Helsinki: Statistics Finland (in Finnish). Ware, J. E., Kosinski, M., Bayliss, M. S., McHorney, C. A., Rogers, W. H., & Raczek, A. (1995). Comparison of methods for the scoring and statistical analysis of SF-36 health profile and summary measures: Summary of results from the medical outcomes study. Medical Care, 33, AS264–AS279. Ware, J. E., Kosinski, M., & Keller, S. D. (1994). SF-36 physical and mental summary scales: a user’s manual. Boston, MA: The Health Institute.
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A comparison of socioeconomic differences in physical functioning and perceived health among male and female employees in Britain, Finland and Japan Pekka Martikainena,b,*, Eero Lahelmac, Michael Marmotb, Michikazu Sekined, Nobuo Nishie, Sadanobu Kagamimorid a
Department of Sociology, Population Research Unit, P. O. Box 18, University of Helsinki, FIN-00014, Finland b Department of Epidemiology and Public Health, International Centre for Health and Society, University College London Medical School, 1-19 Torrington Place, London WC1E 6BT, UK c Department of Public Health, P. O. Box 41, University of Helsinki, FIN-00014, Finland d Department of Welfare Promotion and Epidemiology, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan e Department of Hygiene and Preventive Medicine, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
Abstract We compared the pattern of socioeconomic inequalities in physical functioning and perceived health among male and female employees in Britain, Finland and Japan. Participants were male and female public sector employees in Britain, Finland and Japan, who were economically active and 40–60 year-olds at the time of data collection. We measured perceived health and physical functioning (SF-36 physical component summary) with standardized health questionnaires. The results obtained here reconfirm the similarity of the patterns of ill-health of those with lower socioeconomic status among non-manual men and women in Britain and Finland. These data also provide good evidence for a socioeconomic gradient in ill-health among Japanese non-manual men, although this gradient was less systematic. For Japanese men poorer health of manual workers as compared to non-manual workers was well demonstrated. However, among Japanese women socioeconomic differences in health were small and inconsistent. In conclusion, Britain, Finland and Japan—representing ‘liberal’, ‘Nordic’ and ‘conservative’ welfare state regimes— produce broadly similar patterns of socioeconomic differences in health among men. However, different patterns of labour force participation and welfare provision in different welfare regimes may bring about different patterns of socioeconomic differences in health for working women. This is exemplified by the lack of health inequalities among employed Japanese women. r 2004 Elsevier Ltd. All rights reserved.
Introduction In industrialized western European and north American countries health follows a hierarchical pattern: the *Corresponding author. Department of Sociology, Population Research Unit, P. O. Box 18, University of Helsinki, FIN00014, Finland. Tel.: +358-9-191-23889; fax: +358-9-19123967. E-mail address: pekka.martikainen@helsinki.fi (P. Martikainen).
lower the socioeconomic status, the poorer the health. European comparisons show that the magnitude of socioeconomic inequalities in ill-health and mortality vary among countries (Mackenbach, Kunst, Cavelaars, Groenhof, & Geurts, 1997a; Cavelaars et al., 1998; Kunst, Groenhof, Mackenbach, & Health, 1998; Lahelma et al., 2002). Furthermore, even when similar levels of inequalities in total mortality are observed, very different specific causes may be responsible; alcohol associated causes and cardiovascular diseases being important contributors to overall inequalities (Kunst et al., 1998).
0277-9536/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.socscimed.2004.01.005
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These results highlight the importance of comparative studies in identifying the common and unique determinants of socioeconomic inequalities in health. Comparative studies help us to identify countries or settings with particularly large or small inequalities in health. Such studies can provide a possibility to try to identify the circumstances that are associated with inequalities in health. Small inequalities may, for example, be related to small inequalities in material conditions of life, favourable working conditions and equitable distribution of welfare services. These in turn limit the behavioural choices that individuals can make in terms of smoking, use of alcohol, exercise and intake of fruit and vegetables (Laaksonen, Pr.att.al.a, Helasoja, Uutela, & Lahelma, 2003). Comparing countries may sometimes be the only feasible way to evaluate how policy affects health inequalities, and thus help us to distinguish which among a multitude of factors has the greatest potential to reduce health differences. Simultaneously comparative studies improve our understanding of the limits and generalisability of explanations of inequalities in health obtained in particular national settings. Relatively little comparative research on socioeconomic inequalities in health that include countries of non-European heritage are available. However, analyses of Japan indicate that socioeconomic inequalities in mortality, ill-health and risk factors exist, but the magnitude and pattern of these inequalities are not as consistent as in western countries (Kagamimori, Iibuchi, & Fox, 1983; Kagamimori et al., 1998; Netherlands Central Bureau of Statistics, 1992; Kawakami, Haratani, Hemmi, & Araki, 1992). For example, an earlier comparison of socioeconomic inequalities in risk factors among British and Japanese employed men showed, that although a ‘western inequality pattern’ was observed for some risk factors, it could not be observed for weight (BMI), waist-to-hip-ratio and HDL cholesterol (Martikainen, Ishizaki, Marmot, Nakagawa, & Kagamimori, 2001). Thus, caution is needed against uncritical extrapolation of results on health inequalities from western countries to non-western countries, such as Japan. The aim of this study is to compare the patterns of socioeconomic inequalities in physical functioning and perceived health among male and female government employees in Britain, Finland and Japan. These three countries represent the ‘liberal’, the ‘Nordic’ or ‘social democratic’ and the ‘conservative’ welfare regimes, respectively, each characterised by a different pattern of welfare production and allocation (Esping-Andersen, 1990, 1999). Previous evidence of health inequalities being associated with welfare regimes is inconclusive (Mackenbach et al., 1997a). ‘A welfare regime can be defined as the combined, interdependent way in which welfare is produced and allocated between state, market and family’ (Esping-Andersen, 1999, p. 35). Under this
broad definition of a welfare regimes there are at least three factors that may be put forward as having a significant contribution for socioeconomic differences in health. These relate to the following: (1) differences in the direct material consequences of redistributive income policies and universalistic and egalitarian principles in the provision of social benefits, education and health care; (2) differences in the psychosocial and psychological consequences of these policies in terms of sense of belonging, feelings of cohesion and sense of security; and (3) differences in the working of the labour market in terms of gender segregation, the male ‘bread-winner’ model and the ability of women to participate in paid work.
Data and methods Participants Participants of the Japanese, Finnish and British cohorts were recruited from municipal, provincial and national public sector work places. Because socioeconomic differences in ill-health in Japan are poorly documented, we use data for two different Japanese cohorts. Those invited to participate were sent a standardised self-report health questionnaire. In Japan questionnaires were sent to the employees of a prefecture on the west coast of Japan (Kagamimori, Sekine, Nasermoaddeli, & Hamanisi, 2002), and Takarazuka City (Nishi, Makino, Fukuda, & Tatara, 2003) in 1998–1999 and 1997–1998, respectively. All employees were invited to participate. The response rates were 88% and 83% correspondingly. The Finnish data derived from the Helsinki Health Study baseline survey of municipal employees from the City of Helsinki in 2000 and 2001 (Kivel.a et al., 2001) and aged 40, 45, 50, 55 or 60 at the time of the survey in each year. The response rate was 68%. The British cohort comprised of employees working in the London offices of twenty National Government Civil Service departments and recruited in 1985–1988 (the Whitehall II study) (Marmot et al., 1991). The overall response rate was 73%, although the true response rate is likely to be higher because around 4% of those listed as employees were not eligible as they had moved before the study. For this study we included men and women who participated in the baseline of the Japanese and Finnish studies or in the third phase of the British study (1991– 1993) and were economically active and 40–60 year-olds at that time. Altogether 2255 participants from the prefecture on the west coast of Japan, 1060 from Takarazuka, 5886 from Helsinki, and 6942 from London were included. The cross-sectional nature of these data limit strong causal interpretations of the
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results. Generalisations of our results to national populations should be carried out with caution. Measurement of socioeconomic status In all cohorts information on employment grade—our measure of socioeconomic status—was obtained, and the following hierarchical grades were used: (1) managerial/administrative, (2) professional and semi-professional, (3) clerical employees, and (4) manual workers. In the cohort on the west coast of Japan employment grade was based on the questionnaire of the Japanese national survey for occupations that distinguishes between 13 broad occupational categories. These were allocated into the four grades and were made up of the following specific occupations: (1) managerial grade consisted of provincial government officials in senior positions, such as legislators, governors, accounting officials, directors and heads of division, and heads of section, (2) professional grade consisted mainly of engineers and health care employees, e.g. mechanical, electrical, computer, civil and surveying engineers, physicians, dentists, veterinarians, pharmacists, nurses, midwives and nutritionists, but also judges, social workers, welfare advisers and teachers, (3) general office staff, e.g. clerical workers and accounting clerks, and (4) manual workers were mainly bus, truck and ambulance drivers. In the Takarazuka cohort employment grade was based on questionnaire information on job rank and type of occupation used within the city administration and was classified in the following way: (1) managerial employees at the department director and section chief levels, (2) professionals, e.g. doctors, nurses, teachers and technicians, (3) office based clerical employees below the section chief level, and (4) manual workers, e.g. school janitors, canteen workers, drivers and fire fighters. In the Helsinki cohort employment grade was based on combined information from the personnel register data of the City of Helsinki and questionnaire data. The classification schema was based on hierarchical employment grade levels used in City of Helsinki for office employees, and manual workers were distinguished using the Statistics Finland (Statistics Finland, 1989) classification in the following way: (1) managers in supervisory positions, (2) professionals (e.g. doctors, teachers and social workers) and semi-professionals (e.g. nurses among women, and foremen and technicians among men), (3) clerical employees and other female dominated non-professional occupations within the social and health care (e.g. child minders, assistant nurses and secretaries), and (4) manual workers (e.g. bus drivers, janitors, fire fighters, cleaners and canteen workers). On the basis of questionnaire information three grades were obtained in London based cohort of civil servants by collapsing the 12 non-industrial salary based
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grade levels used in the Civil Service in the following way: (1) managerial grade consisted of unified grades 1– 6 (Permanent Secretary to Senior Principal), (2) professional and executive group was made up of unified grade 7 (Principal), senior executive officers, higher executive officers and executive officers, and (3) clerical grade consisted of clerical officers and clerical assistants. There were no manual workers within the British national government civil service. With these data employment grade classifications among non-manual employees could not be obtained using strictly harmonised instruments. Nevertheless, the employment grade variables that we have used here are strictly hierarchical in all cohorts. The data do not enable us to draw conclusions on the exact magnitude of employment grade differences in health, but are reliable for analyses of the broad hierarchical patterns of socioeconomic health inequalities. Measurement of health outcomes Physical health functioning was measured with the SF-36 questionnaire which covers issues relating to physical, psychological and social functioning and is coded into eight scales: physical functioning, role limitations due to physical problems, social functioning, bodily pain, general mental health, role limitations due to emotional problems, vitality, and general health perceptions. These eight scales are summarised into physical and mental functioning component summaries by a method based on factor analysis (Ware, Kosinski, & Keller, 1994; Ware et al., 1995). For all cohorts we used US general population weights to calculate physical component summaries. Low scores imply low physical functioning and a mean of 50 is observed in the US general population (Ware et al., 1995). For Finland and Japan we used SF-36 translations (Hagman, 1996; Fukuhara, Bito, Green, Hsiao, & Kurokawa, 1998a; Fukuhara, Ware, Kosinski, Wada, & Gandek, 1998b). In the Whitehall II study the correlation between physical component and the physical functioning score was 0.75, and the correlation between the physical and mental components was 0.04. For Helsinki these correlations were 0.81 and 0.03 and for both of the Japanese cohorts 0.67 and 0.10, respectively. In all cohorts physical health functioning was strongly associated with longstanding illness and history of heart disease (angina, heart attack, hypertension; results from the author). For these analyses poor physical health functioning was defined as having a score below the 25th percentile. The percentile cutpoint was obtained from data that pool the four study cohorts. Perceived general health was obtained from a question with equal wording in each cohort: ‘In general would you say your health is’ with five response alternatives ranging from ‘excellent’ to ‘poor’. Perceived
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health reflects a broad range of medical and other health status information available to the individual ranging from knowledge of existing diseases through cognitive and affective characteristics of individuals and personality (Manderbacka, 1998). The measure is regarded as suitable for comparative purposes, because it is simple to ask and has produced consistent results in different countries (de Bruin, Pichavet, & Nossikov, 1996; Idler & Benyamini, 1997; Jylh.a, Guralnik, Ferrucci, & Jokela, 1998). For these analyses the outcome was categorised as 0=good, very good and excellent and 1=fair and poor. Statistical methods The association between employment grade and our two measures of health were analysed using logistic regression in STATA statistical package (Stata Reference Manual, 1992). We enter employment grade as a categorical explanatory variable to the models; four categories for the Finnish and Japanese cohorts and three categories for the British cohort. We adjusted for categorical age in single years. Among men the highest grade (administrative/managerial) was used as the reference category. However, among women we used the second highest employment grade (professional) as the reference, because the highest grade had only very few observations in the Japanese cohorts. The results are presented in terms of odds ratios together with 95% confidence intervals. Analyses were conducted separately in men and women and for each cohort. As a summary index—here referred to as the inequality index—for the employment grade differences in health among non-manual workers we estimated a continuous logistic regression coefficient for employment grade with each category being assigned values 1– 3. This method gives a more stable effect estimate since data for all employment grades are used. It has an intuitive interpretation as the increase in ill-health for each step down the employment grade ladder, e.g. a value of the index of 1.50 obtained from logistic regression analyses indicates that ill-health increases by a factor of 1.50 (expressed in terms of the odds ratio) from one grade to the next (Mackenbach & Kunst, 1997b). The index imposes linearity on the association between employment grade and health. Departures from linearity can be assessed from Tables 2 and 3. The index is a measure of total effect, as it takes into account both the strength of the health differences between groups as well as the distribution of the population into these groups.
In particular, very few Japanese women occupy higher grades. These differences are partly due to the higher socioeconomic composition of the British civil servants recruited from London based national government departments, and differences in the occupational structure between city and provincial employees. Among men and women differences in the prevalence of fair or poor perceived health and poor physical functioning were observed, with British civil servants having better health than the other cohorts. Partly these differences reflect differences in the socioeconomic composition of these cohorts mentioned above, but partly they may also reflect true differences in health status, or cultural differences in health reporting. Among non-manual male employees a consistent employment grade gradient in fair or poor perceived health (Table 2) was observed in all the four cohorts. Odds ratio for perceived health in the clerical grade as compared to the administrative/managerial grade varied between 1.61 (95% CI 0.97–2.70) in Helsinki to 3.20 (95% CI 2.31–4.43) in London. In the analyses of women we have used the professional grade as the reference group, because of the bottom heavy distribution of women, particularly in Japan. Among Japanese non-manual women negligible grade differences in fair or poor perceived health were observed, while in Helsinki and London lower grade women had consistently worse perceived health. For poor physical functioning (Table 3) a typical western pattern of health inequalities again emerged among non-manual Finnish and British men. However, in the two Japanese cohorts these differences were smaller and less systematic. Among Japanese women the differences between non-manual grades were inconsistent; i.e. the grade gradients were in the opposite directions in the two cohorts. Poorer physical functioning in the lower non-manual grades were observed in the Helsinki and the London cohorts among women. In the Helsinki and both Japanese cohorts a manual grade could also be identified. In all these cohorts manual men had poorer perceived health and poorer physical functioning than all non-manual men, with the exception of manual men in the cohort on the west coast of Japan whose perceived health was similar to that of the professional employees. The poorer health of Japanese manual women was less clear.
Discussion Socioeconomic differences among men
Results Proportionally more British employees work in the top grade than Japanese and Finnish employees (Table 1).
For men earlier studies comparing socioeconomic inequalities based on occupational social position in Britain and Finland suggest that the pattern and magnitude of health inequalities in these two countries
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Table 1 Mean age, prevalence of poor physical functioning, prevalence of fair or poor perceived health, and distribution (%) of study participants by employment grade West coast of Japan Men Mean age Prevalence of poor physical functioning Prevalence of fair or poor perceived health Employment grade Non-manual Administrative/managerial Professional Clerical Manual All N Women Mean age Prevalence of poor physical functioning Prevalence of fair or poor perceived health Employment grade Non-manual Administrative/managerial Professional Clerical Manual All N
Takarazuka
Helsinki
London
49.2 24.6 27.6
48.6 24.2 37.3
49.9 25.7 28.8
48.5 13.2 9.3
12.8 45.3 30.5 11.4 100.0 1800
9.3 20.8 29.6 30.4 100.0 794
16.5 45.8 10.7 27.1 100.0 1182
47.7 45.6 6.7 — 100.0 4802
48.5 37.4 35.1
48.5 39.5 40.3
49.1 33.3 26.8
49.7 27.7 14.1
1.1 61.7 30.4 6.8 100.0 708
1.1 21.1 40.9 36.8 100.0 266
7.9 38.2 43.1 10.8 100.0 4704
15.9 45.0 39.1 — 100.0 2140
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. Table 2 Age-adjusted odds ratios of fair or poor perceived health by employment grade
Men N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades Women N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades
West coast of Japan
Takarazuka
Helsinki
London
OR
OR
OR
OR
95% CI
1796 1.00 1.63 2.56 1.57 1.56
821
1.10–2.42 1.68–3.89 0.97–2.53 1.30–1.89
706 0.59 1.00 1.04 0.74 1.08
95% CI
1.00 1.83 2.26 2.28 1.42
1210
1.11–3.04 1.40–3.65 1.43–3.63 1.12–1.80
287 0.11–3.14 0.73–1.48 0.38–1.45 0.77–1.51
—a 1.00 1.01 2.15 1.28
95% CI
1.00 1.17 1.61 2.41 1.27
4807
0.79–1.72 0.97–2.70 1.60–3.63 0.98–1.65
4852 — 0.51–2.01 1.05–4.38 0.65–2.54
0.96 1.00 1.50 2.20 1.35
95% CI
1.00 1.49 3.20 — 1.69
1.20–1.84 2.31–4.43 — 1.45–1.97
2150 0.73–1.26 1.29–1.75 1.78–2.72 1.21–1.51
0.69 1.00 1.65 — 1.58
0.45–1.05 1.26–2.16 — 1.31–1.92
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. a Odds ratio is not estimated as it would be based on three observations.
is broadly similar for perceived health, but inequalities are perhaps somewhat larger in Finland for limiting long-standing illness (Lahelma, Arber, Rahkonen, &
Silventoinen, 2000). However, differences in perceived health by household income were possibly a little larger in Britain (Rahkonen, Arber, Lahelma, Martikainen, &
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Table 3 Age-adjusted odds ratios of poor physical functioning by employment grade
Men N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades Women N Non-manual Administrative/managerial Professional Clerical Manual Inequality index for non-manual grades
West coast of Japan
Takarazuka
Helsinki
London
OR
OR
OR
OR
95% CI
1800
95% CI
794
95% CI
1182
95% CI
4802
1.00 1.40 1.47 1.56
0.96–2.06 0.97–2.22 0.98–2.48
1.00 1.15 1.05 1.99
0.65–2.04 0.60–1.82 1.19–3.32
1.00 1.58 1.83 2.83
1.04–2.40 1.05–3.20 1.82–4.41
1.00 1.27 1.96 —
1.06–1.51 1.45–2.65 —
1.15
0.95–1.40
0.95
0.72–1.26
1.38
1.05–1.81
1.35
1.18–1.54
708 0.39 1.00 0.68 0.93 0.75
266 0.07–2.10 0.47–0.98 0.49–1.77 0.53–1.05
—a 1.00 1.80 2.63 2.46
4704 — 0.84–3.86 1.17–5.91 1.14–5.29
1.03 1.00 1.58 2.10 1.38
2140 0.80–1.33 1.38–1.82 1.71–2.59 1.24–1.53
0.67 1.00 1.25 — 1.33
0.49–0.91 1.01–1.54 — 1.15–1.54
Japanese, British and Finnish cohorts of employed men and women aged 40–60 years. a Odds ratio is not estimated as it would be based on three observations.
Silventoinen, 2000). Overall both countries have socioeconomic inequalities in health that are of average European level (Cavelaars et al., 1998; Mackenbach et al., 1997a). Some evidence indicates that mortality differences may be larger in Finland than in the UK (Mackenbach et al., 1997a). The results obtained here reconfirm the broad similarity of occupation based socioeconomic (employment grade) gradients in health among non-manual men in these two countries. Among Japanese men, a tendency for lower grade non-manual employees to have poorer health was also observed, although this was somewhat less consistent for physical functioning. An earlier comparison of socioeconomic inequalities in risk factors among British and Japanese employed men is consistent with this by showing that a western inequality pattern was observed for many, but not necessarily all risk factors among Japanese employees (Martikainen et al., 2001). Furthermore, these data show that manual male workers in Japan have poorer health than non-manual male workers. This is consistent with poorer physical functioning and perceived health of Finnish male manual workers observed in this study, and evidence elsewhere (Lahelma et al., 2000; Mackenbach et al., 1997a). Socioeconomic differences among women For women the two European cohorts differed markedly from the Japanese cohorts. Clear employment grade differences were observed for Finnish and British
non-manual employees. While among Japanese women socioeconomic differences in health were small and inconsistent. It is worth pointing out that comparative studies of socioeconomic inequalities of women’s health are rare and have mainly used standard survey data (e.g. from national level of living surveys) on national populations of working and non-working women. In addition, because of problems in allocating non-working women into occupation based socioeconomic categories these studies have typically focussed on other measures of socioeconomic status, such as education (Cavelaars et al., 1998; Lahelma et al., 2002). The three countries that we have studied represent three different welfare regimes as proposed by EspingAndersen. Britain, Finland and Japan belong to the ‘liberal’, the ‘Nordic’ or ‘social democratic’ and the ‘conservative’ welfare regimes, respectively (EspingAndersen, 1990, 1999). There are several characteristics of welfare regimes that may have significance for socioeconomic differences in employed women’s health, particularly in Japan. In Japan inconsistent or small socioeconomic differences in health were observed. For physical functioning the two cohorts showed inequalities in opposite directions and for perceived health the differences were nonexistent. Also the level of health among manual workers was inconsistent among Japanese women. The Japanese ‘conservative’ welfare regime is characterised by low female attachment to paid work. Female labour force
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participation is low and part-time work is common (Iwai, Fujioka, Yoshinaga, & Sugihashi, 2002; OECD). Furthermore, the status of the jobs that women occupy are disproportionately at the bottom of the occupational hierarchy (Iwai et al., 2002). For example, in these data about 1% of women were in administrative or managerial jobs. Accordingly, wage differences between men and women are large, and there is a strong dependence on family responsibility in welfare provision geared around the well-earning male ‘bread-winner’ (EspingAndersen, 1999; Jacobs, 1998). Thus, the paid jobs women hold are likely to have lesser importance on their general welfare and material quality of life and are accordingly of lesser importance in driving socioeconomic inequalities in health. The results suggest that analyses of socioeconomic inequalities in women’s health in Japan and possibly in ‘conservative’ welfare regime countries more generally may be better carried out using household based measures of socioeconomic status, such as household income or the socioeconomic status of the person in the household with the highest status. Occupation based socioeconomic differences in perceived health and physical functioning among British and Finnish female non-manual employees were quite similar in this study. To some extent this finding was unexpected, because contrary to our results, previous findings on the working and as well as non-working female populations categorized according to the women’s own current or previous occupation based social position indicate that differences in perceived health and limiting long-standing illness in Finland are somewhat larger than in Britain (Lahelma et al., 2000). The larger occupation based socioeconomic differences in health among Finnish women can be explained in terms of female labour market characteristics. The Nordic social democratic welfare regime, particularly Finland, is characterised by exceptionally high full-time labour force participation, and universal social benefits (e.g. daycare and parental leave arrangements) that enable women to combine motherhood and paid employment. In Britain publicly funded daycare facilities are modest and female labour force participation is much lower than in Finland. Accordingly, this stronger attachment of Finnish women to the labour market may be associated with greater discriminatory power of women’s own socioeconomic position in Finland than in Britain. Our finding of quite similar socioeconomic differences in health in the two cohorts may be partly due to the closer comparability of our public sector cohorts than two samples of national populations in terms of, e.g. working conditions and occupational distributions. However, a study using education as a measure of socioeconomic status in 11 countries (Cavelaars et al., 1998) found great similarity in differences in perceived
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health, and another study on household income indicated somewhat larger inequalities in Britain (Rahkonen et al., 2000). Thus, no clear overall picture on the relative strength of socioeconomic inequalities in women’s health in Britain and Finland emerges. Methodological considerations International comparisons of socioeconomic differences in health may be affected by data comparability problems. The strength of our data is that information on health outcomes was collected with identical instruments in all cohorts. Furthermore, all cohorts consisted of public sector employees, and thus form more homogeneous and comparable populations. A potential weakness of these data is that within non-manual employees employment grade classifications could not be obtained using strictly harmonised instruments. Nevertheless, the employment grade structure that we have used here is strictly hierarchical in all cohorts, and although caution is needed in drawing conclusions on the exact magnitude of employment grade differences in health, our findings are reliable in assessing the broad patterns of socioeconomic health inequalities. Further comparative studies using different indicators of socioeconomic position—such as education and household based indicators—are needed. Furthermore, these results are compatible with previous comparative work on men showing that risk factors for major diseases are less consistently associated with socioeconomic hierarchy in Japan than in western Europe (Martikainen et al., 2001). In addition, direct generalisations of these findings to the respective national populations should be carried out cautiously. All cohorts consist of employed men and women, a healthy sub-set of the general population (Martikainen & Valkonen, 1999), and are recruited from regions that may not be representative of the respective countries more generally.
Conclusion Our results emphasize the importance of comparative studies of socioeconomic inequalities in health among men and women in different national settings. We have shown that socioeconomic differences in ill-health vary between Japanese, Finnish and British employees, and that particularly Japanese women show little evidence of the western pattern of inequality in health so far. Britain, Finland and Japan—representing ‘liberal’, ‘Nordic’ and ‘conservative’ welfare state regimes— produce broadly similar patterns of socioeconomic differences in health among men. However, different patterns of labour force participation and welfare provision in different welfare regimes may be associated
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with different patterns of socioeconomic differences in health for employed women. We could find no evidence that inequalities in health are smaller in a cohort from the ‘Nordic’ welfare regime (see also Mackenbach et al., 1997a). The results indicate that different social structural contexts and historical settings shape the pattern of socioeconomic inequalities in health.
Acknowledgements This work is part of the European Science Foundation program on Social Variations in Health Expectancy in Europe, in particular the working group on Macrosocial Determinants of Morbidity and Mortality. The Helsinki Health Study is supported by grants from the Academy of Finland, Research Council for Health (48119, 48553 and 53245) and the Finnish Work Environment Fund (99090). The Whitehall II study has been supported by grants from the Medical Research Council, British Heart Foundation, Health and Safety Executive, National Heart Lung and Blood Institute (HL36310), National Institute on Aging (AG13196), Agency for Health Care Policy Research (HS06516), The New England Medical Centre: Division of Health Improvement, Institute for Work and Health, Toronto, and the John D and Catherine T MacArthur Foundation Research Networks on Successful Midlife Development and Socioeconomic Status and Health. PM has a fellowship and a grant (70631, 48600) from the Academy of Finland. MM is supported by a United Kingdom MRC Research Professorship. We wish to thank participating employees, and the research teams in all collaborating centers. Elina Nihtil.a and Peppiina Saastamoinen helped in carrying out the analyses and preparing the tables.
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