12.3 Socio-economic inequalities in health in developed countries: the facts and the options
Oxford Textbook of Public Health
Socio-economic inequalities in health in developed countries: the facts and the options
Johan P. Mackenbach
The purpose of this chapter
Outline of the chapter
The facts: description
The facts: explanation
Selection versus causation
The options: how to build a strategy to reduce inequalities in health?
Justification and objectives
Package of policies and interventions
Evaluation and monitoring
The options: experiences in the United Kingdom and the Netherlands
The purpose of this chapter
Socio-economic inequalities in health, i.e. systematic differences in morbidity and mortality rates between those with a lower and a higher socio-economic status, have been studied extensively around the world in the past decades. Inequalities in health have been documented from the United States (Davey Smith et al. 1996) to the former Soviet Union (Dennis et al. 1993), from The Netherlands (Mackenbach 1992) to New Zealand (Pearce et al. 1991), and from Brazil (Duncan et al. 1995) to Bangladesh (Bairagi et al. 1993). The emphasis of research in this field has gradually shifted from description to explanation and, although the number of countries for which results of explanatory studies are available is still limited, a general understanding of the factors involved has emerged. Childhood circumstances, material factors, health-related behaviours, and psychosocial factors have all been shown to contribute significantly to the explanation of socio-economic inequalities in health (Carroll et al. 1993; Kaplan and Keil 1993; Davey Smith et al. 1994; Vågerö and Illsley 1995; Macintyre 1997).
More recently, a start has been made on the systematic development of strategies to reduce inequalities in health (Whitehead and Dahlgren 1991; Dahlgren and Whitehead 1992; Benzeval et al. 1995). It has become clear that waiting until all explanatory questions have been answered would imply that action will probably never occur, and so both researchers and health policy-makers have searched for sensible recommendations in the face of limited knowledge.
It is the purpose of this chapter to give a brief review of the available evidence on the description and explanation of socio-economic inequalities in health, and then to present the current (1999) state of the art with regard to the available options for reducing socio-economic inequalities in health.
Historical evidence suggests that socio-economic inequalities in health are not a recent phenomenon, but it is only relatively recently, during the nineteenth century and on the basis of mortality statistics, that socio-economic inequalities in health were ‘discovered’. Before that time socio-economic inequalities in morbidity and mortality health went unrecognized, and there was even a general perception that all human beings were equal before death. This is illustrated by the Dances of Death or Danses Macabres, which were a favourite theme in western and central European literature and painting during the late Middle Ages (Mackenbach 1995a). These Dances of Death typically portray the living according to their social standing, and each of them is accompanied by a corpse or skeleton symbolizing death (Fig. 1). According to the historian Huizinga, the Dance of Death ‘reminded the spectators of the frailty and the vanity of earthly things’, but at the same time ‘preached social equality as the Middle Ages understood it, Death levelling the various ranks and professions’ (Huizinga 1976).
Fig. 1 The Dance of Death of Guillaume Marchant (fragment). (Source: Mackenbach 1995a.)
The awareness of socio-economic inequalities in health dates back to the nineteenth century, when great figures in public health such as Villermé in France, Chadwick in England, and Virchow in Germany devoted a large part of their scientific and practical work to this issue (Ackerknecht and Virchow 1953; Coleman 1982; Chave 1984). This was made possible by the availability of national population statistics, which permitted the calculation of, for example, mortality rates by occupation or by city district. The only reliable source of mortality data in the general population that existed before national population registers were implemented (i.e. generally before the nineteenth century) consists of parish registers of baptisms and burials. An analysis of socio-economic inequalities in mortality on the basis of data from seventeenth century Geneva shows that the life expectancy of children born in the lowest occupational class was only 18 years, and that of the highest occupational class was 36 years (Perrenoud 1975). Data for other European cities from the eighteenth century confirm this picture of huge differences in mortality rates between persons of higher and lower social rank (Schultz 1991).
It is not certain whether socio-economic inequalities in mortality also existed before the seventeenth or eighteenth centuries, but it is difficult to believe that they did not. The Middle Ages were a period characterized by frequent mortality crises, arising from three frequently interlinked causes, i.e. war, pestilence, and famine. Of the three causes, famine, or more generally undernutrition, provides the most obvious link with socio-economic conditions. The rich certainly had a lower risk of dying from undernutrition than the majority of the population, which was probably malnourished even in ‘normal’ years. In addition, anecdotal evidence suggests that mortality during epidemics, particularly the plague, was higher in the lower social classes. Reports of health commissions in plague-ridden towns frequently mention that there were large differences in mortality between rich and poor (Cipolla and Zanetti 1972). Therefore the notion, embedded in the Dances of Death, that all human beings were equal before death must primarily be interpreted in metaphysical terms.
Since the nineteenth century the magnitude of socio-economic inequalities in mortality has certainly declined in absolute terms; owing to the general decline of mortality, the absolute difference in mortality rates between those with a high and those with a low socio-economic position has become much smaller. It is less clear whether relative inequalities in mortality have also declined over time; relative risks of dying between those with a low and those with a high socio-economic position have remained remarkably stable. During recent decades there has even been a clear increase of relative inequalities in mortality in many developed countries (Valkonen 1993; Lang and Ducimetière 1995; Regidor et al. 1995; Vågerö and Lundberg 1995; van de Mheen et al. 1996; Drever and Bunting 1997). This is partly due to the social patterning of the ischaemic heart disease epidemic: this probably started in the higher socio-economic groups, then diffused into the lower socio-economic groups, and when the epidemic had reached its peak (about 1970) the decline also started in the higher socio-economic groups before diffusing into the lower socio-economic groups (Marmot et al. 1978; Stallones 1980; Marmot and McDowall 1986; Wing et al. 1986; Mackenbach et al. 1989).
As a result, at the start of the twenty-first century all developed countries are faced with substantial socio-economic inequalities in mortality (and many other indicators of health problems). These are perceived by many as unfair, and in any case as an enormous challenge to public health.
Outline of the chapter
The available evidence on the description and explanation of socio-economic inequalities will be reviewed briefly. Because of space limitations it will be impossible to give a complete survey of the international literature, for which the reader is referred to a number of recent review papers (Carroll et al. 1993; Kaplan and Keil 1993; Davey Smith et al. 1994; Vågerö and Illsley 1995; Macintyre 1997). Here, the emphasis will be on giving an internationally representative overview of socio-economic inequalities in morbidity and mortality in industrialized countries, and on presenting some explanatory frameworks that help to structure the available empirical evidence as well as the options for interventions and policies. The chapter then develops a systematic framework for a strategy to reduce socio-economic inequalities in health, highlighting the choices that have to be made in the areas of justification and objectives, choice of policies and interventions, and evaluation and monitoring. The final section illustrates some of these principles on the basis of recent examples from the United Kingdom and The Netherlands.
The facts: description
Many countries perform health interviews—level-of-living or multipurpose surveys with questions on both socio-economic status (education, occupation, income) and self-reported morbidity (e.g. self-assessed health, chronic conditions, disability). Analysis of these data shows that inequalities in self-reported morbidity are substantial everywhere, and always in the same direction: persons with a lower socio-economic status have higher morbidity rates (Illsley and Svensson 1990; Mielck and do Rosario Giraldes 1993; Lahelma and Arber 1994; Kunst et al. 1995).
Within western Europe the risk of ill health is 1.5 to 2.5 times higher in the lower half of the socio-economic distribution than in the upper half. For example, in Sweden the risk of chronic conditions is 1.85 times higher among men with primary or lower secondary education than among men with higher secondary or tertiary education. When the extremes of the socio-economic distribution are compared (Fig. 2), the size of the inequalities becomes even more dramatic. Substantial inequalities in health are found in all countries included in this figure, from Spain to Finland and from Great Britain to Italy, emphasizing the tremendous importance of this public health problem. Surprisingly, substantial inequalities in self-reported morbidity are also found in the Nordic countries, with their long histories of egalitarian socio-economic and health care policies (Cavelaars et al. 1998a,b). Similar results are found in central and eastern Europe; for example, socio-economic inequalities in self-reported morbidity in the Czech Republic, Estonia, and Hungary are about the same as in most western European countries (Groenhof et al. 1996).
Fig. 2 Inequalities in less-than-good self-assessed health by level of education in 10 European countries, by sex (age range 25–69 years). The relative index of inequality represents the odds ratio of less-than-good self-assessed health for those at the bottom of the social hierarchy (here measured on the basis of educational achievement) compared with those at the top. (Source: Mackenbach et al. 1997.)
While these nationally representative data are based on self-reports, similar patterns are found in other studies using more objective assessments of morbidity, such as the incidence of ischaemic heart disease (Kaplan and Keil 1993; Lynch et al. 1996; Marmot et al. 1997) or cancer (Davey Smith et al. 1991; van Loon et al. 1995).
Similar findings have been reported for mortality, the harder but rarer outcome measure,. Socio-economic inequalities in mortality of considerable magnitude are found in all countries with available data. For example, the excess risk of premature mortality among middle-aged men in manual occupations ompared with those in non-manual occupations ranged from 33 to 71 per cent in a recent comparative study (Fig. 3(a)). On the basis of ‘relative’ differences there is no evidence for smaller inequalities in mortality in the Nordic countries, but Sweden does have rather low ‘absolute’ differences in mortality owing to its low average death rates (Fig. 3(b)) (Mackenbach et al. 1997).
Fig. 3 Inequalities in total mortality by occupational class in 10 European countries, middle-aged men: (a) relative inequalities; (b) absolute inequalities. E&W, England and Wales. (Source: Kunst 1997.)
Mortality data permit a breakdown by cause of death, which may help in exploring possible explanations of inequalities in mortality. An analysis by cause of death reveals a striking north–south pattern within western Europe (Fig. 4). In the Nordic countries, England and Wales, and Ireland, half or more of the socio-economic gap in total mortality is due to an excess risk of cardiovascular diseases in the lower socio-economic groups. In France, Switzerland, Italy, Spain, and Portugal cardiovascular diseases account for a small fraction of the higher risks of premature mortality in the lower socio-economic groups only, while cancers (but not lung cancer) and gastrointestinal diseases (such as liver cirrhosis) have a large share in the excess risks (Kunst et al. 1998, 1999). These data suggest that there are likely to be some differences in the explanations of socio-economic inequalities in mortality in the north and the south of Europe. Currently, cardiovascular risk factors such as smoking and intake of animal fat are likely to be important in northern Europe, with excessive alcohol consumption being important in the south (Cavelaars et al. 1997).
Fig. 4 Contribution of specific causes of death to inequalities in total mortality by occupational class in 10 European countries, middle-aged men. Contribution is measured as the proportion of the difference between manual and non-manual rates of total mortality which is due to a specific cause-of-death group. (Source: Kunst et al. 1998.)
This international pattern can also be interpreted as an expression of different stages of epidemiological development. In northern Europe (and in the United States) mortality from cardiovascular diseases has not always been higher in the lower socio-economic groups. In the 1950s and 1960s ischaemic heart disease mortality was higher in the higher socio-economic groups, and this only reversed during the late 1960s and 1970s (Marmot et al. 1978; Stallones 1980; Marmot and McDowall 1986; Wing et al. 1986; Mackenbach et al. 1989). It is possible that the situation in southern Europe represents an earlier stage of epidemiological development, and that the smaller size of inequalities in cardiovascular disease mortality will turn out to be a temporary phenomenon.
In central and eastern Europe socio-economic inequalities in mortality are equally large or larger than those in western Europe. The real outlier seems to be Hungary, which had by far the largest inequalities in mortality among the countries included in a recent comparative study (Kunst 1997; Mackenbach et al. 1999). Among middle-aged men the risk of dying was 165 per cent higher in manual than in non-manual occupations. These very large relative differences combine with the high average death rates in Hungary to form extremely large absolute differences in mortality between the higher and lower socio-economic groups.
Substantial inequalities in mortality were also seen in the United States, but the size of these inequalities was not clearly different from those observed in western Europe. In view of the variations observed within Europe, it is tempting to speculate that the heterogeneity of the United States population, with its immigrants from all parts of Europe as well as from many other parts of the world, has averaged out the experience of subpopulations with larger and smaller inequalities in mortality (Kunst et al. 1999).
Many studies of socio-economic inequalities in mortality have been confined to men, partly because the most frequently used socio-economic classification, that based on occupation, can less easily be applied to women. From the studies that have included women, it has become clear that inequalities in mortality also exist among women but tend to be smaller than those among men (Moser et al. 1988; Dahl 1991; Koskinen and Martelin 1994; Martikainen 1995; Mackenbach et al. 1999). In studies that used occupational class as an indicator of socio-economic status this may be an artefact, but similar findings were reported from a few studies that used educational level or material living standards as socio-economic indicators. As Fig. 5 illustrates, women have smaller relative inequalities in mortality for most causes of death, including neoplasms, but not for cardiovascular diseases. The smaller inequalities in total mortality among women are the result of smaller inequalities for many causes of death, but also of differences between women and men in cause-of-death pattern. Neoplasms and cardiovascular diseases account for a large majority of all deaths among both men and women, but neoplasms, for which inequalities in mortality are relatively small among women and among men, have a larger share of total female mortality than of total male mortality (Koskinen and Martelin 1994; Mackenbach et al. 1999).
Fig. 5 Inequalities in cause-specific mortality by level of education among men and women in the United States: relative risk for up to lower secondary education versus upper secondary education and higher. (Source: Mackenbach et al. 1999.)
Nearly all causes of death have higher rates of mortality in the lower socio-economic groups. One of the very few exceptions is breast cancer, for which mortality rates tended to be higher among women in the higher socio-economic groups, perhaps because they adopted ‘modern’ fertility and breast-feeding practices that increase breast cancer risk before women in the lower socio-economic groups (van Loon et al. 1994). However, recent evidence suggests that this pattern is reversing, and that among younger generations of women risks are higher in the lower socio-economic groups (Heck and Pamuk 1997).
The international patterns highlighted in this section suggest not only that there are some differences between explanations of socio-economic inequalities in health in different countries, but also that interventions and policies to reduce socio-economic inequalities in health may differ. Although the basic socio-economic structures are similar, the pathways through which low socio-economic status affects health are different, and therefore interventions targeting more proximal determinants of socio-economic inequalities in health should be adapted to the situation prevailing in the country.
As was shown in the previous two paragraphs, both morbidity and mortality rates are higher in the lower socio-economic groups. These two health aspects combine in even larger inequalities in health expectancy, because people in lower socio-economic groups do not only live shorter lives but also spend a larger portion of their life in ill-health. While socio-economic inequalities in life expectancy usually amount to 3 to 7 years, differences in, for example, disability-free life expectancy amount to more than 10 years between the highest and lowest socio-economic groups (Valkonen et al. 1997; Sihvonen et al. 1998).
The facts: explanation
Selection versus causation
Research on explanations for socio-economic inequalities in health needs hypotheses, if not theories, and one important source of inspiration for such hypotheses has been the Black Report, published in 1980 in the United Kingdom by a committee chaired by Sir Douglas Black (Townsend et al. 1988a). In this report four types of explanation were proposed: artefact, social selection, cultural or behavioural, and materialist.
Artefact explanations have largely been refuted by research carried out since the publication of the Black Report. Artefact explanations imply that the relationship between socio-economic status and health is produced by the process of measurement, and does not exist in reality. An example is inaccuracies in data on numerators and denominators used for the calculation of socio-economic inequalities in mortality, leading to an overestimation of mortality in the lower socio-economic groups. However, good-quality data, in which these and other problems have been avoided, show substantial socio-economic inequalities in health, and suggest that while bias may from time to time occur, the overall picture is not seriously distorted by measurement problems (Fox et al. 1985; Bloor et al. 1987).
The situation is slightly different with regard to social selection explanations. These imply that health determines socio-economic status, instead of socio-economic status determining health (Fig. 6). There is some evidence that during social mobility, i.e. changes in socio-economic position during an individual’s life compared with either his or her parents (intergenerational mobility) or with him- or herself at an earlier point in time (intragenerational mobility), selection on (ill-)health may occur, with people who are in ill-health being less likely to move upward and/or more likely to move downward (Illsley 1955; Luft 1974; Stern 1983; Wadsworth 1986; van de Mheen et al. 1999). This is perhaps more likely with income as an indicator of socio-economic position than with occupational class or educational level; in the latter case, health problems in adult life cannot affect current level at all.
Fig. 6 ‘Selection’ and ‘causation’ mechanisms in the explanation of socio-economic inequalities in health.
While the occurrence of health-related selection is undisputed, it is less clear what its contribution to the explanation of socio-economic inequalities in health is. It is only in a few studies that this has been investigated directly, and these have shown that the contribution to inequalities in health by occupational class is small (Fox et al. 1982; Wadsworth 1986; van de Mheen et al. 1999). This is at least partly due to the fact that while those who move downward do indeed have worse health than those who remain in their social class of origin, they have better health than those who are already in their class of destination (Goldman 1994).
More recently, a different form of selection has been proposed that may have a stronger impact on socio-economic inequalities in health—’indirect selection’. Indirect selection implies that social mobility is selective on determinants of health, not on health itself (West 1991). Intelligence could be an example; educational careers are partly dependent on intelligence, and intelligence is also likely to be a determinant of health, for example through sensible behaviour. Excessive alcohol consumption could be another example; employment and career prospects are negatively affected by alcohol abuse, which also may lead to health problems. There is very little empirical evidence yet on the occurrence and importance of indirect selection, and so it is difficult to assess its importance for the explanation of socio-economic inequalities in health. It is also important to take into account the fact that the health determinants on which indirect selection takes place, such as intelligence or excessive alcohol consumption, could themselves be related to living circumstances during the earlier stages of life. Indirect selection would then be part of a mechanism of accumulation of disadvantage over the life course (Davey Smith et al. 1994).
Implications for policy
The importance of selection mechanisms for socio-economic inequalities in health is not only a scientific issue, but is also relevant for public health and social policy. If ill-health leads to downward social mobility, and if this contributes to the higher rates of health problems in the lower socio-economic groups, then measures that limit the impact of ill-health on, for example, employment prospects or occupational careers will help in reducing inequalities in health.
Material, psychosocial, and behavioural factors
Longitudinal studies in which socio-economic status has been measured before health problems are present, and in which the incidence of health problems is measured during follow-up, show higher risks of developing health problems in the lower socio-economic groups, and suggest ‘causation’ instead of ‘selection’ as the main explanation for socio-economic inequalities in health (Rose and Marmot 1981; Fox et al. 1982, 1985; Marmot et al. 1991). This ‘causal’ effect of socio-economic status on health is likely to be mainly indirect, through a number of more specific health determinants that are differentially distributed across socio-economic groups. Here, the Black Report made a distinction between ‘cultural/behavioural explanations’ (a higher prevalence of health-damaging behaviours, such as smoking, in the lower socio-economic groups) and ‘materialist/structural explanations’ (less favourable material circumstances, such as housing conditions, in the lower socio-economic groups) (Townsend et al. 1988a). Since the publication of the Black Report, research has advanced considerably and produced a clearer view of the ‘intermediary’ factors involved in causal explanations. In addition to the behavioural factors and the ‘material’ living circumstances, which were given prominence in the Black Report, psychosocial factors have been recognized as important contributors to socio-economic inequalities in health. Figure 7 summarizes the interrelationships between socio-economic status, these three groups of intermediary factors, and health.
Fig. 7 The role of material, psychosocial, and behavioural factors in the explanation of socio-economic inequalities in health.
‘Material’ factors, i.e. exposure to low income and to health risks in the physical environment, also contribute to the explanation of socio-economic inequalities in health. Despite the fact that low income is such a fundamental aspect of low socio-economic status, the evidence for its role in generating health inequalities is far from complete. Income-related indicators of socio-economic status, such as level of household income, house and car ownership, or area-based measures of deprivation, have been demonstrated to be relatively strong predictors of ill-health (Townsend et al. 1988b; Carstairs and Morris 1989; Goldblatt 1990; Davey Smith et al. 1994). How low income affects health, and the relative importance of pathways related to low income, is far from clear, however. It is obvious that income may affect exposure to a wide range of health determinants, either directly (through ability to purchase health-promoting goods, such as safe housing and a healthy diet) or indirectly (through the psychosocial effects of the experience of relative deprivation), but there has been surprisingly little empirical research into these mechanisms. Most of the recent research into the health effects of income inequality has focused on the aggregate relationship between the extent of income inequality in a population, and its average mortality level or life expectancy (Fig. 8) (Wilkinson 1992; Kaplan et al. 1996; Kennedy et al. 1996). This research has shown that after accounting for differences between populations in average income level, a wider disparity in income within a population is associated with a higher mortality level and a lower life expectancy. While this suggests that reducing income inequalities may not only reduce health inequalities but also improve the overall health level of a population, it is not yet clear how the association is to be explained. It may be due to psychosocial effects of income inequality (more relative deprivation, less social cohesion) or to the lack of investment in human resources, which is usually found in regions with more income inequality (when a more equal income distribution is the result of progressive taxation, there will be more public money for education, health care, etc.) (Wilkinson 1996; Lynch and Kaplan 1997).
Fig. 8 The association between income inequality and life expectancy. (Source: Wilkinson 1996.)
The recent interest in psychosocial pathways between low socio-economic status and ill-health has been stimulated by the observation that socio-economic inequalities in morbidity or mortality cannot be explained entirely by well-known behavioural or material risk factors for disease. This is particularly true for cardiovascular disease outcomes, where risk factors such as smoking, high serum cholesterol, and high blood pressure explain less than half of the socio-economic gradient in mortality (Rose and Marmot 1981; Davey Smith et al. 1990; Lynch et al. 1996). Together with the observation that inequalities in health have a generalized character, in the sense that the risks for diseases with widely different aetiologies are similarly socially patterned, this has given rise to the hypothesis that a lower socio-economic status may be associated with a higher ‘generalized susceptibility’ to disease (Marmot et al. 1984). This generalized susceptibility could be due to psychosocial factors; being in a low socio-economic position may be a psychosocial stressor, which, through biological or behavioural pathways, could lead to ill-health (Brunner and Marmot 1999).
One of the areas where there is clear evidence for psychosocial effects of being in a low socio-economic position is the work environment. Karasek’s demand–control model predicts that a high level of psychological job demands combined with a low level of decision latitude (e.g. low level of decision authority) will lead to higher risks of stressful experience and subsequent physical illness, particularly ischaemic heart disease (Karasek et al. 1981). Jobs characterized by high demands and, particularly, low control are more prevalent in the lower socio-economic strata, and these psychosocial stressors in the work environment have indeed been shown to account for part of the social gradient in health (Fig. 9) (Marmot et al. 1997; Schrijvers et al. 1998).
Fig. 9 The contribution of psychosocial job characteristics to the explanation of socio-economic inequalities in the incidence of coronary heart disease (CHD) in men. (Data from Marmot et al. 1997.)
In addition to the work environment, other spheres of life may also produce higher levels of stress in the lower socio-economic groups, as is evident from the higher prevalence of life events, chronic stressors, and daily hassles (Kessler and Cleary 1980; Stronks et al. 1998; Brunner and Marmot 1999). It is still unclear how psychosocial stress induces ill-health in the lower socio-economic groups. One possibility is that this is an indirect effect, through health-related behaviour; smoking, excessive alcohol consumption, and obesity may all to some extent be a reaction to, or way of coping with, psychosocial stress (Graham 1995; Lynch et al. 1997; Stronks et al. 1997; Jarvis and Wardle 1999). Another possibility is that psychosocial stress induces ill-health directly, through biological mechanisms. The biological response to stress leads to release of adrenaline (through the sympatho-adrenal pathway) and cortisol (through the hypothalamic–pituitary–adrenal axis), and these have important effects on many organs, including blood pressure, blood clotting, and immunity. It has been hypothesized that such mechanisms underlie the elevated rates of, for example, cardiovascular disease in the lower socio-economic groups (Brunner and Marmot 1999).
Health-related behaviours, such as smoking, diet, alcohol consumption, and physical exercise, are important ‘proximal’ determinants of socio-economic inequalities in health. As Fig. 10 shows, smoking is more prevalent in the lower socio-economic groups, at least in most European countries (van Reek and Adriaanse 1988; Pierce 1989; Cavelaars et al. 2000). However, there are some exceptions, particularly in southern Europe, where smoking seems to be more prevalent in the higher socio-economic groups, particularly among women. These patterns are likely to be related to differences between countries in the progression of the smoking epidemic. This started in northern Europe, among men and in the higher socio-economic groups, and then diffused into southern Europe, to women, and to the lower socio-economic groups. The cessation of smoking followed a similar pattern, and the ‘reverse’ patterns for women in southern Europe as seen in Fig. 10 are probably due to the fact that southern Europe is in an earlier stage of the smoking epidemic. Unfortunately, the situation in younger cohorts suggests that countries in southern Europe are catching up quickly. Because of the strong impact of smoking on health socio-economic differences in smoking contribute importantly to socio-economic inequalities in health, at least in some countries.
Fig. 10 Inequalities in smoking by level of education in 10 European countries, by sex and age group. Prevalence rate differences for up to lower secondary education versus upper secondary education and higher. Source: Cavelaars et al. 2000.)
The contribution of diet to inequalities in health is less clear. In many countries people in lower socio-economic groups consume less fresh vegetables and fruits (Bolton-Smith et al. 1991; Osler 1993), but data on fat consumption do not suggest consistent differences between socio-economic groups (Hoeymans et al. 1996; Davey Smith and Brunner 1997). On the other hand, obesity is very strongly associated with socio-economic status, with much higher prevalence rates of obesity in the lower socio-economic groups, particularly in richer countries (Sobal and Stunkard 1989; Cavelaars et al. 1997). Data on socio-economic differences in alcohol consumption are also not always consistent, but frequently lower socio-economic groups have higher rates of both abstinence and excessive alcohol consumption (Cummins et al. 1981; Hupkens et al. 1993; Hoeymans et al. 1996; Cavelaars et al. 1997). Cause-of-death patterns suggest a substantial contribution of excessive alcohol consumption to inequalities in mortality in at least some countries, such as Finland (Mäkelä et al. 1997) and countries in southern Europe (Kunst et al. 1998). Finally, lack of leisure-time physical activity is more prevalent in the lower socio-economic groups (Holme et al. 1981; Tenconi et al. 1992; Lynch et al. 1997), but it is unclear to what extent this is compensated for by higher rates of work-related physical activity. It is unlikely that such compensation is substantial in the rich service economies of northern Europe, but it may still be in poorer countries.
Implications for policy
Following the publication of the Black Report there has been a sharp debate on the relative importance of material versus behavioural factors for the explanation of socio-economic inequalities in health. In some countries there has been a tendency among policy-makers to use evidence on the importance of health-related behaviour for arguing that reducing inequalities in health is an individual instead of a public responsibility (Macintyre 1997). As a reaction, some researchers have tried to de-emphasize the importance of health-related behaviour. However, it can easily be shown that this is a false antithesis; the higher rates of smoking in the lower socio-economic groups may be a way of coping with unfavourable material circumstances (see Fig. 7) (Graham 1995; Stronks et al. 1997; Schrijvers et al. 1999). Health-related behaviour is a more ‘proximal’ risk factor, but may nevertheless be an important element of the causal chain linking low socio-economic status to ill-health.
This is clearly illustrated by the results of some of the international comparisons described above. Within Europe the Nordic countries are characterized by relatively large inequalities in cardiovascular disease mortality, and this is likely to be due to the strong social patterning of behavioural risk factors, which is seen in these countries (Kunst et al. 1998, 1999; Cavelaars et al. 2000). Egalitarian social and economic policies do not seem to protect a population against strong social gradients in health-related behaviour. There may even be a causal connection, in the sense that a reduction of inequalities in wealth and income reduces the opportunities for status acquisition on the basis of material advantage, which may lead to an increased tendency towards differentiation in cultural terms, for example in lifestyles (Bourdieu and Translated by Nice 1984). In any case, specific interventions and policies may be needed to reduce inequalities in health-related behaviour, even in the presence of maximum efforts to reduce inequalities in material factors.
Our discussion of the explanation of socio-economic inequalities in health has so far largely ignored the importance of time; disease usually occurs as a result of prolonged exposure to risk factors, and exposure to these risk factors may be the result of long individual life histories. Explanatory schemes such as those of Fig. 7, apply to a relatively small section of the life of an individual (e.g. middle age) and are based on explanatory studies, which also involve similarly short follow-up periods. Recently, the limitations of this approach for understanding socio-economic inequalities in health have been recognized, as a result of studies demonstrating an association between intrauterine and infant conditions and disease in middle age (Barker 1992) and of long-term follow-up studies of birth cohorts showing how health in adulthood reflects circumstances at earlier stages of life (Power et al. 1991).
Figure 11 illustrates how a life-course perspective could be applied to socio-economic inequalities in health. Socio-economic status in childhood (e.g. father’s occupational class) determines socio-economic status in adulthood (despite social mobility many adults are in the same occupational class as their parents), and it has been shown that lifelong exposure to low socio-economic status carries higher risks of ill-health than exposure during one stage of life only (Davey Smith et al. 1997). Many health-related behaviours (e.g. smoking) are formed in adolescence, i.e. under the influence of socio-economic status in childhood, and it has been shown that socio-economic inequalities in health-related behaviour are partly the result of different exposures to low socio-economic status in childhood (van de Mheen et al. 1998a). The same is likely to apply to other intermediary factors, such as coping styles, locus of control, and other psychosocial factors (Bosma et al. 1999). Health may have a certain continuity across the life-course, with ill-health in adulthood tracking back to ill-health in childhood and therefore to determinants acting in earlier stages of life (Wadsworth 1997; van de Mheen et al. 1998b). Socio-economic inequalities in health may thus be due to the cumulative effect of disadvantage across the life-course.
Fig. 11 A life-course perspective on the explanation of socio-economic inequalities in health.
Health during one stage of the life-course may also affect socio-economic status in a later stage, owing to processes of health-related selection (see the discussion of selection and causation above). The life-course perspective enables us to see more clearly the iterative nature of some of these processes and suggests a ‘co-evolution’ of social position and health, taking away the sharp contradiction between ‘selection’ and ‘causation’ explanations (Vågerö and Illsley 1995; van de Mheen et al. 1998c).
Implications for policy
At first sight, the life-course perspective suggests that interventions and policies targeting children and young adults should be prioritized. Many studies employing a life-course perspective have demonstrated that some of the roots of socio-economic inequalities in health can be found in the first decades of life. Interventions and policies aiming to reduce material or health disadvantage in childhood and adolescence, or breaking the chain between social and health development, are likely to contribute to smaller socio-economic inequalities in health over the entire life-course. On the other hand, the life-course perspective also suggests that all phases of the life-course are important. If it is true that the health disadvantage in the lower socio-economic groups is the result of cumulative health damage occurring over the entire life-course, then it is also important to reduce health damage occurring in later stages of life. There are critical periods, and while some of these are in early life (e.g. birth, move from primary to secondary school, entry into labour market), others are in later life (e.g. occupational change, onset of chronic illness, retirement). Social security systems have an important role to ensure that these critical periods do not result in cumulative disadvantage (Blane 1999).
The options: how to build a strategy to reduce inequalities in health?
During the 1990s several attempts were made to develop strategies for reducing inequalities in health (Whitehead 1990; Dahlgren and Whitehead 1992; Benzeval et al. 1995). Outside the United Kingdom there have also been some attempts at developing strategies for reducing inequalities in health, particularly in The Netherlands where a systematic research-based approach has been pursued by successive national governments of different political compositions (Mackenbach 1994a). These national experiences are reviewed in more detail in the final section.
This section is devoted to a more general discussion of the elements that a strategy for reducing socio-economic inequalities in health should contain: a specification of its justification and objectives, a package of policies and interventions, and facilities for evaluation and monitoring. Important choices have to be made for each of these elements.
Justification and objectives
What is a fair distribution of health?
It is important to note that it cannot be taken for granted that socio-economic inequalities in health are unfair. According to Whitehead’s normative analysis, inequalities in health can only be labelled ‘unjust’ if they are perceived as both ‘unacceptable’ and potentially ‘avoidable’ (Table 1). Socio-economic inequalities in health which arise as a result of natural biological variation or of freely chosen health-damaging behaviour will not commonly be perceived as ‘unacceptable’. However, inequalities in health resulting from health-damaging behaviour not chosen freely, or exposure to health hazards in the environment, or impaired access to health care services will be perceived as ‘unacceptable’ and are also potentially avoidable (Whitehead 1990).
Table 1 Whitehead’s scheme for judging the (un)fairness of socio-economic inequalities in health
This type of reasoning is generally accepted as a basis for policy-making on socio-economic inequalities in health. However, the ‘perception’ of acceptability of inequalities in health will very much be determined by one’s theory of justice. Implicit in this type of reasoning is an egalitarian perspective, in which the fairness of a certain distribution of goods is judged on the basis of the equality of the outcome of the process of distribution. Regardless of how the process occurs (with only few exceptions, such as freely chosen health-damaging behaviour), more ill-health in the lower than in the higher socio-economic groups is seen to be unfair simply because some people have less of the highly valued good ‘health’ than others. In contrast, in a strictly libertarian perspective the justness of a certain distribution of goods is judged on the basis of characteristics of the process of distribution. The main criterion is whether the process of distribution is determined by ‘freely negotiated transfers in the market-place’. Some people are more successful in using their opportunities than others; on the basis of their value in the employment market they obtain well-paid and safe jobs, and they can afford to live in comfortable houses in nice neighbourhoods. That others do not and as a result experience more ill-health can only be labelled unfair, in this view, if there has not been freedom of opportunity (de Jong and Rutten 1983).
It is important to analyse different political ideologies with regard to their implications for the judgement of socio-economic inequalities in health, and to choose one’s normative justification carefully, if only because this may increase one’s capacity for building broad coalitions. One interesting approach is to regard health as a ‘resource’, not as a ‘good’ or an end in itself (Sen 1985, 1990). Health then determines a person’s capacity to operate in the various ‘market-places’ of society, and even a strict adherence to the libertarian theory of justice would probably agree that more ill-health in the lower socio-economic groups may be a danger to the free operation of markets. This is particularly the case when ill-health really determines a person’s opportunities in life, as for children born to parents in lower social classes who because of ill-health may have less successful school careers. In the case of adults, one could argue that the higher frequency of ill-health in the lower social classes should be a reason for concern among libertarians, because ill-health is an important determinant of employment prospects.
What should the goal be?
There are also various options with regard to the (quantitative) specification of the objectives of policies and interventions to reduce socio-economic inequalities in health. The target agreed upon by the member states of the World Health Organization (WHO) European Region was that ‘by the year 2000, the actual differences in health status … should be reduced by at least 25 per cent, by improving the level of health of disadvantaged … groups’ (WHO 1985). Although this target has been immensely helpful in putting inequalities in health on the policy agenda, it has also been widely criticized because of its vagueness.
If one wants to be more precise, there is a large choice of possible measures for the size of socio-economic inequalities in health (Mackenbach and Kunst 1997). One of the most important distinctions is that between relative measures, such as rate ratios, and absolute measures, such as rate differences. This distinction is illustrated in Fig. 3 on the basis of an international comparison of inequalities in mortality among middle-aged men. Absolute inequalities are much smaller in Sweden than in Ireland, not because relative inequalities are smaller but because the average rate of mortality is smaller in Sweden. It can be argued that absolute inequalities are more relevant for public health policy than relative inequalities; it is the size of the absolute inequalities that directly influences a person’s life chances, and therefore the primary aim should be to reduce absolute inequalities in health.
If one accepts this line of reasoning, and specifies objectives in terms of a reduction of absolute differences, the number of available policy options increases substantially. Any policy or intervention that reduces average rates of mortality or morbidity, without changing the size of the relative inequalities, will help in achieving this objective. Investing in overall improvements of population health, while taking care to achieve similar relative rates of improvement in higher and lower socio-economic groups, is a potentially powerful way of reducing inequalities in health and does not even require an explicit commitment to reducing inequalities in health.
What can realistically be achieved?
The WHO equity target was agreed upon in 1984 and has not been reached. Is this because national governments have not made serious efforts, or because the target was too ambitious? A recent review of policies and interventions to reduce socio-economic inequalities in health in Finland, The Netherlands, Spain, Sweden, and the United Kingdom has shown that, despite good intentions in some countries, the scale and intensity of the efforts have been very modest (Mackenbach and Droomers 1999).
One could also rightly argue that the target was far too ambitious. In many countries there is evidence of an, apparently spontaneous, widening of socio-economic inequalities in health. This widening has occurred not only in countries with increasing income inequalities, such as the United Kingdom, but also in countries with narrowing income inequalities, such as Finland (Valkonen et al. 1993). Although some of the widening of health inequalities may be an adverse effect of the introduction of libertarian economic policies, it is likely that the underlying ‘spontaneous’ trends would have counteracted any beneficial effect of serious efforts to implement the WHO equity target.
What can realistically be achieved is a function of, first, underlying ‘spontaneous’ trends and, second, the potential effect of interventions and policies that will be implemented. Making such estimates is a difficult exercise, and there is a great need for formal methods to estimate the potential effect of interventions and policies to reduce inequalities in health. Recently, the WHO renewed its equity target to be included in the new Health 21 Strategy (WHO 1999) (Box 1). While the target has become more specific, it is still very ambitious and is unlikely to be achieved unless spontaneous trends and systematic interventions and policies work together in the coming decades.
Box 1 Equity targets in the WHO Health 21 strategy (WHO 1999)
Target 2: equity in health
By the year 2020, the health gap between socio-economic groups within countries should be reduced by at least one-fourth in all member states, by substantially improving the level of health of disadvantaged groups.
2.1 The gap in life expectancy between socio-economic groups should be reduced by at least 25%.
2.2 The values for major indicators of morbidity, disability and mortality in groups across the socio-economic gradient should be more equitably distributed.
2.3 Socio-economic conditions that produce adverse health effects, notably differences in income, educational achievement, and access to the labour market, should be substantially improved.
2.4 The proportion of the population living in poverty should be greatly reduced.
2.5 People having special needs as a result of their health, social, or economic circumstances should be protected from exclusion and given easy access to appropriate care.
Package of policies and interventions
Any attempt to reduce socio-economic inequalities in health should of course be based on an understanding of their causes. The explanatory models discussed earlier suggest the following options for intervention and policy:
to reduce inequalities in education/occupation/income
to reduce the effect of ill-health on education/occupation/income
to reduce inequalities in specific determinants (‘intermediary’ material, psychosocial, and behavioural factors).
A fourth option could be added to this:
to increase supply of health care in lower socio-economic groups (Mackenbach 1994a).
Choosing between these options, and between the specific interventions and policies within each option, may be a difficult task.
‘Upstream’ or ‘downstream’ solutions?
At first sight offering extra health care is not the most attractive option for reducing inequalities in health. It is expensive and can never totally eliminate the problem because people will have to fall ill before extra health care can repair the damage. Also, really effective health care interventions are scarce. It has all the disadvantages of a ‘downstream’ solution, with only one serious advantage—decisions about reallocation of resources within the health sector are at least partly under the control of health policy-makers.
In contrast, changing the basic socio-economic distributions is intuitively much more attractive. Where one knows the fundamental causes of health problems, it is appropriate to address these directly, and to try to reduce the prevalence of a low socio-economic status, by preventing children from leaving school with no or low qualifications, by increasing employment opportunities and abolishing low-status jobs, and/or by reducing poverty. It would seem that this is likely to have more leverage than addressing more immediate causes, let alone offering extra health care. Each fundamental cause is linked to a variety of more immediate causes, and through these to an even larger variety of health effects. Also, one avoids the possibility that after one of the more immediate causes has been eliminated, other immediate causes take its place because the same fundamental causes are still in operation. It has all the advantages of an ‘upstream’ solution, with only one serious disadvantage—decisions about basic socio-economic distributions are not taken by health policy-makers.
This intuitive comparison of ‘downstream’ and ‘upstream’ solutions may be theoretically valid, but it is important to note that there is no empirical evidence to support the claim that ‘upstream’ interventions are more effective for reducing health inequalities than ‘downstream’ interventions. Therefore choices will have to be made on other grounds as well, including well-documented effects on non-health-related outcomes of upstream policies or simply political feasibility.
Lack of evidence on effectiveness of interventions and policies is a general problem in this area. As the final section will show, policy-makers can choose from very large ‘menus’ of specific interventions and policies. These large menus certainly have positive aspects. They provide policy-makers with considerable decision latitude, which may increase their possibilities for political coalition building as well as for recruiting different organizations to achieve their objectives. On the other hand, these large menus also betray the uncertainty of their authors with regard to what would really help (Mackenbach 1995b). Recent reviews have shown that the evidence base for policy-making is rather unsatisfactory; evaluation studies reported in the international literature cover only a few of the options currently considered, suffer from methodological weaknesses, and do not always show positive effects of interventions (Arblaster et al. 1995; Gepkens and Gunning-Schepers 1996). An informal meta-analysis of studies fulfilling basic methodological criteria suggests that interventions that combine different approaches (e.g. health education combined with structural measures) are most effective in reducing inequalities in health (Table 2).
Table 2 Overview of evidence on effectiveness of interventions to reduce socio-economic inequalities in health
Evaluation and monitoring
How to evaluate?
As the earlier section on packages of policies and interventions has shown there is a great need here for ‘evidence-based’ policies and interventions. However, the complexity of evaluation should not be overlooked. This complexity follows from two specific characteristics of policies and interventions to reduce socio-economic inequalities in health.
The first is that the aim is not to reduce some average value of a health outcome, but to reduce a difference in health between groups. In the simpler case of interventions, which aim to reduce an average value, a minimum of four measurements is required: one ‘before’ and one ‘after’ measurement in an experimental and a control group. In this more complex situation, a minimum of eight measurements is required: one ‘before’ and one ‘after’ measurement in both higher and lower socio-economic groups in both the experimental and the control population (Mackenbach and Gunning-Schepers 1997). This design can only be simplified if some relatively strong assumptions are fulfilled. For example, if one can assume that the intervention does not influence the higher socio-economic groups, four measurements in the lower socio-economic group could be sufficient.
The second is that many policies and interventions will have to be ‘collective’ or population based in nature. This implies that assignment to the intervention or policy cannot be done on an individual basis, but only on a collective basis (e.g. schools, neighbourhoods, or even whole countries). Consequently, the randomized controlled trial will often not be the design of first choice. Sometimes the design of the community intervention trial can be used, when a select allocation of schools or neighbourhoods to either an experimental or control condition can be performed (Koepsell et al. 1992, 1995). With increasing levels of aggregation, however, experimentation becomes less and less feasible; in the extreme example of changes in national legislation a fully experimental evaluation of the policy is clearly impossible. This implies that experimental designs other than the classical type will frequently have to be employed. Quasi-experimental designs, in which the evaluator does not control the allocation of units to the experimental and control condition but chooses control units carefully to match the experimental units, are likely to be helpful alternatives (Campbell and Stanley 1963; Cook and Campbell 1979). The same applies to carefully designed observational studies, in which different types of evidence are creatively combined to support conclusions on effectiveness (‘triangulation’). It is extremely important that the impossibility of employing classical experimental designs is not used as an excuse for not evaluating at all.
How to increase learning speed?
No single country has the capacity of contributing more than a fraction of the necessary knowledge to support strategies for reducing inequalities in health. This is not only a matter of restricted manpower or financial resources for research, but also of restricted opportunities for implementing policies and interventions. Some policies can be implemented in some countries, but not in others because they have already been implemented or are politically completely unfeasible. Different countries present different opportunities for evaluation, and therefore international exchange and perhaps co-ordination is necessary. There is an important role for international agencies, such as the European Union, to support this development.
How to remain visible?
Reducing inequalities in health requires systematic and prolonged action, and the likelihood of continuing commitment from policy-makers can be enhanced if socio-economic inequalities in health remain clearly visible to policy-makers as well as to the general public (including the media). Continuous monitoring of inequalities in health by bureaux of statistics and other agencies is likely to help in achieving this, as well as putting inequalities in health on the agendas of, for example, health research funding agencies (Gunning-Schepers 1989).
The options: experiences in the United Kingdom and The Netherlands
In this section we will review the experiences of two countries, the United Kingdom and The Netherlands, in the field of interventions and policies to reduce socio-economic inequalities in health. These countries have been chosen because their experiences have been relatively well documented in the international literature, and also because they represent very different traditions. The United Kingdom is characterized by a long tradition of research in this area, dating back to the nineteenth century, which has resulted in a very rich knowledge base that has benefited researchers and policy-makers in many other countries as well. Another characteristic, perhaps not unrelated to this long tradition, is the strong political polarization of the debate on socio-economic inequalities in health in the United Kingdom. To their surprise, foreign observers will discover that different types of explanation have become linked to different political ideologies. In The Netherlands, on the other hand, there is a much shorter tradition of research on socio-economic inequalities in health, as in many other countries in continental Europe. Since the late 1980s a focused effort has been made to build a knowledge base for policy-making, and so far strong political polarization of the debate has not occurred. There is a broad consensus that inequalities in health are unfair, and that ways should be found to reduce inequalities in health. To their surprise, foreign observers will discover that the Dutch hope to find an engineering solution.
The Black Report not only presented an influential explanatory framework, but also a set of recommendations, which has very much shaped the debate on reducing inequalities in health both inside and outside the United Kingdom (Macintyre 1997). Its recommendations focused on improving material living conditions and were very unwelcome to the Conservative government to which they were issued (Townsend et al. 1988a). For years there was little room for discussing policies to reduce inequalities in health, but in the early 1990s the political climate gradually changed. Whitehead’s work for the WHO mentioned above (Whitehead 1990; Whitehead and Dahlgren 1991) was taken a step further in a King’s Fund report (Benzeval et al. 1995), which discussed a wide range of policy options for one example in each of four different policy areas: physical environment (example: housing), social and economic influences (example: income maintenance), ‘barriers to adopting a healthier personal lifestyle’ (example: smoking), and ‘access to appropriate and effective health and social services’ (example: the role of the National Health Service).
When after many years of Conservative government a Labour government came to power in 1997, it made a clear commitment to reducing social inequalities, including socio-economic health inequalities. It asked a committee chaired by Sir Donald Acheson to perform an ‘independent inquiry into inequalities in health’ and to develop suggestions for policies aiming to reduce health inequalities. These were published in 1998 and subsequently partly incorporated in national (health) policies. The Acheson Report (Box 2) is the most comprehensive of all the reports cited so far. Interestingly, while it acknowledges the importance of health-related behaviour for the explanation of socio-economic inequalities in health, it does not include a chapter on lifestyle factors (these are treated as a component of other areas). Instead, and surprisingly, it has a chapter on mobility and transport, and discusses various target groups. It contains 123 recommendations in 11 areas for ‘future policy development’, and has been criticized for its resemblance to a shopping list (Davey Smith et al. 1998; Shaw et al. 1999).
To varying degrees, each of these reports published in the United Kingdom shows awareness of the need to provide evidence for its recommendations. Typically, this is observational evidence on the importance of the target factor for socio-economic inequalities in health, and not experimental evidence on the effectiveness of the proposed interventions and policies. The Acheson Report contains the most systematic attempt at reviewing the (quasi-)experimental evidence available to support its recommendations. Although such evidence is available for only a minority of the recommendations, the report clearly points the way to a more systematic evaluation of the interventions it recommends (Anonymous 1998).
Because the New Labour government that came into power in 1997 committed itself to the reduction of social inequality in general, the United Kingdom also offers interesting opportunities for evaluating social and economic policies with a potential impact on health. Table 3 gives a summary of a number of recent initiatives that may contribute to a reduction of socio-economic inequalities in health. Some of the measures, such as the introduction of a national minimum wage, have been taken in other countries long before 1997, but it would be interesting to all countries to know whether this has an effect on inequalities in health. Other measures, such as the area-based programmes targeting different ‘Action Zones’, are innovations, which if successful may become a source of inspiration for many other countries (Graham et al. 1999).
Table 3 Recent social and economic initiatives in the United Kingdom, which may help in reducing socio-economic inequalities in health
Box 2 A summary of the recommendations of the Acheson Report
Independent inquiry into inequalities in health
Chair: Sir Donald Acheson
Report: November 1998
I. General recommendations
II. Areas for future policy development
Poverty, income, tax, and benefits
Housing and environment
Mobility, transport, and pollution
Nutrition and the Common Agricultural Policy
Mothers, children, and families
Young people and adults of working age
III The National Health Service
that all policies should be evaluated in terms of their impact on health inequalities…
policies which will further reduce income inequalities…
the further development of high quality pre-school education…
good management practices which lead to increased control, variety and appropriate use of skills in the workforce…
policies to improve insulation and heating systems
measures to encourage walking and cycling
policies which reduce the sodium content of processed foods
increases in the real price of tobacco…
development of services which are sensitive to the needs of ethnic minority groups…
policies to reduce the fear of crime and violence…
giving priority to a more equitable allocation of NHS resources
Socio-economic inequalities in health were a non-issue in The Netherlands until the early 1980s. In 1980, The Netherlands’ Society for Social Medicine celebrated its fiftieth anniversary with a conference on socio-economic inequalities in health, which approximately coincided with the work on the Black Report in the United Kingdom. In the same year, the results of a study on inequalities in morbidity and mortality between neighbourhoods in Amsterdam were published, and to the surprise of many clearly demonstrated the existence of socio-economic inequalities in health in The Netherlands (Lau-Ijzerman et al. 1981). Although there was no direct follow-up to these initiatives, they laid the basis for the later adoption by The Netherlands’ government of the Health for All policy targets of WHO, including the equity target. As a result, in 1986 the Ministry of Public Health included a paragraph on inequalities in health in a major policy document for the very first time.
From then on, initiatives were taken from inside the Ministry to put equity in health on the political as well as the research agenda (Gunning-Schepers 1989). In 1987 a conference was held under the aegis of the prestigious Scientific Council for Government Policy, and major press coverage was arranged for the publication of its proceedings (Wetenschappelijke Raad 1987). The report recommended, among other things, a national research programme which the Ministry launched in 1989. The main objective of this programme was to generate more knowledge on socio-economic inequalities in health in The Netherlands, both descriptive and explanatory. The programme was completed in 1994, and its results were reported widely in national and international journals, as well as in a book (Mackenbach 1994b) and a report to the Ministry (Programme Committee Socio-Economic Health Differences 1994). The latter contained a number of general policy recommendations covering all four areas mentioned above.
An evaluation of the research programme showed that it had a measurable impact on the scientific community, at least in the short run. Widespread involvement of research groups with socio-economic inequalities in health was generated. As a result the number of scientific publications on the topic had clearly increased, far more than could have been expected from studies directly funded from the programme. Also, the knowledge base had increased substantially. Not only the size and pattern of socio-economic inequalities in health in The Netherlands, but also the role of housing and working conditions, psychosocial factors, and lifestyle factors in the explanation of socio-economic inequalities in health, had been documented (Mackenbach 1994a).
The report on the programme also recommended launching a second programme focusing on the development and evaluation of interventions to reduce socio-economic inequalities in health. The new government, which came into power in 1994, adopted this recommendation, and sponsored a second national research programme, which ran from 1995 to 2000. Table 4 gives an overview of the interventions that were subjected to (quasi-)experimental evaluation. As is clear from this list, these are mostly small-scale interventions in specific settings. Although an attempt has been made to cover all the main policy areas, the focus is on interventions targeting specific determinants (intermediary factors). Results of evaluation studies will become available in 2000.
Table 4 Overview of interventions evaluated in the second national research programme on socio-economic inequalities in health in The Netherlands
As this chapter has shown, socio-economic inequalities in health are a major challenge to public health. Inequalities in health are substantial and universal, and are unlikely to disappear spontaneously. Their explanation is only partly understood, and many of the factors are resistant to intervention. Nevertheless, the ambition has arisen to try to reduce inequalities in health. This requires systematic and prolonged efforts which in multiparty democracies will only be possible if broad coalitions can be built. Political will should be mobilized, not only to implement the recommendations for interventions and policies, but also to sponsor the research necessary to evaluate the effects. After documenting the existence of inequalities in health and studying their explanation, there is one further challenge to researchers in this area—assessing the effectiveness of interventions aimed at reducing these inequalities in health.
Attempts at reducing inequalities in health cannot but be illustrations of Rudolf Virchow’s famous dictum ‘Medicine is a social science, and politics is nothing than medicine at a grand scale’ (Ackerknecht and Virchow 1953). Let us try to make this a rational form of medicine.
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