Class Gradient Research Articles

Socio‐economic and ethnic factors in stillbirth and neonatal mortality in the NE Thames Regional Health Authority (NETRHA) 1983

All stillbirths and neonatal deaths occurring in the North East Thames region were studied in 1983. This report describes the socio-economic and ethnic differences in that cohort. The stillbirth and neonatal mortality rates of babies born to fathers of social class V (16.8 per 1000 total births) was almost double that of social class I fathers (8.6 per 1000 total births). The most marked social class gradient was seen in the macerated stillbirth groups. Of particular concern was the extremely high stillbirth and neonatal mortality rate for women born in the Indian subcontinent. This was most evident in Pakistani women who had a stillbirth plus neonatal mortality rate of 17.3 per 1000 total births, almost twice that of the women born in the UK (9.0 per 1000 total births). Again, as with social class, macerated stillbirths appeared to contribute disproportionately to the excess mortality. Mortality rates were aggregated into four birthweight specific groups. Asian women had higher mortality rates in the higher birthweight groups, whereas in the lower birthweight group their babies did slightly better. This study indicated that the special needs for working class and ethnic minority mothers within NE Thames were not being met, and the Regional Health Authority was strongly recommended to review services to these groups.

Malignant Melanoma in England: Risks Associated with Naevi, Freckles, Social Class, Hair Colour, and Sunburn

In a case-control study in the Midlands of England, 195 subjects with superficial spreading or nodular melanoma were compared to age- and sex-matched controls chosen from all inpatients or outpatients in hospitals serving the defined source population. Significant increases in melanoma risk, after adjustment for other factors, were seen in association with total naevi on the arms (odds ratio (OR), for 15+ naevi compared to none = 3.8), intense freckling as an adult (OR = 6.2), and as a child (OR = 6.0), and higher social class (OR = 2.4). Positive single factor associations were also seen with light or red hair colour, tendency to sunburn easily, and a history of sunburn at ages 8-12, although these were not significant when adjusted for the other factors. No significant effect was seen with naevi greater than 6 mm, or with raised naevi, when adjusted for total number of naevi. Total arm naevi and density of freckling had independent effects, consistent with a multiplicative effect, the OR in those with 10+ naevi and heavy freckling being 20.8. The risk associated with red hair was independent of naevi, but associated with freckling. The strongest association with sunburn history was seen with a history of sunburn in childhood, with sunburn at later times, having smaller effects, or none. These results shows that freckling and social class as well as naevi are strong and independent risk indicators for melanoma. These associations were generally consistent by type of melanoma, sex, age, and extent of regular exposure of the body site affected, although the social class gradient was observed neither for nodular melanoma nor for melanomas occurring on the most exposed body sites.

Social class and health in youth: Findings from the west of Scotland twenty-07 study

The assumption that social class inequalities in health are a persistent feature of the life-course has been questioned in a recent issue of this journal. On the evidence of mortality and chronic illness, the pattern in youth in Britain appears to be characterised by the lack of class differentials, a striking contrast to early adulthood where the familiar picture of health inequalities is observed. The possibility that this finding of relative equality in youth is a consequence of the limited, and potentially inappropriate, health indicators used has now been tested on a cohort of 15-year-olds in the West of Scotland. On a range of indicators, from subjective assessments to objective physical measures, very little evidence of class variation in health is found. The possible transience of the youth pattern is, however, indicated by findings from a cohort of 35-year-olds in the same study, among whom marked class gradients in health are apparent. Possible explanations for the transformation of a pattern of relative class equality in youth into one of inequalities in adulthood are discussed.

Pattern of cervical screening utilization in Italy.

The pattern of cervical screening utilization in Italy was analyzed using data from the 1986-1987 National Health Survey on the basis of a sample of 27,455 women aged 20 to 79 randomly selected within strata of municipality of residence and age in order to be representative of the whole Italian population. Overall, about 17% of women aged 20 to 79 were screened per year, for a total of 3.5 to 4 million cervical smears per year. The highest frequency was reported in younger middle age, about one in four women being screened per year in the age groups 30 to 49, and there was a substantial decline above age 50. Cervical smear rates were higher in Northern areas (22%), where mortality from cervical cancer is lower, than in the Centre (16%) and South (11%) of the country. Further, there was a strong positive social class gradient in the utilization of cervical screening, in relation to both education and occupation. In spite of the absence of any organised mass screening program, cervical screening is a relatively common procedure among Italian women. However, this study provides further quantitative evidence of a markedly irrational utilization of non-organized cervical screening, which tends to end up selectively used by the groups in which cervical cancer is less common.

The diets of pregnant and post-pregnant women in different social groups in London and Edinburgh: calcium, iron, retinol, ascorbic acid and folic acid.

Dietary records were obtained twice in pregnancy and once post-partum, from 265 women in all social classes in London and Edinburgh. Some Edinburgh women, and lactating women, showed the higher levels of calcium intake. For iron, retinol, ascorbic acid and folic acid, there was a consistent and significant regional and social class gradient in intakes. This favoured English women in 'non-manual' social groups, leaving the Scottish 'manual' class, after pregnancy, with the lowest intakes. Mean intakes of Ca and Fe were consistently below the current UK recommended daily amount (RDA). Intakes of retinol were all above it, and ascorbic acid intakes ranged above and below the RDA.

The socioeconomic status of women attending a New Zealand colposcopy clinic.

An analysis of a group of predominantly Caucasian women with cervical intraepithelial neoplasia grade 3 lesions seen at the Dunedin Hospital Colposcopy Clinic during a period when it was the only colposcopic service in the region, showed that patients in the lowest socioeconomic class, as judged by two parameters unique in New Zealand were overrepresented. This finding is in agreement with the social class gradient for cervical cancer and precursor lesions observed in other countries. Poverty, more liberal sexual activity and smoking may be factors in the genesis of cervical neoplasia amongst the women studied. In providing cervical smear facilities for at-risk women, special provision should be made for women in the lowest social stratum.

Mortality and social class in Sweden--exploring a new epidemiological tool.

Total mortality, mortality from coronary heart disease (CHD), cerebrovascular disease, and other causes of death, were examined for three social groups and ten socio-economic groups in Sweden. The study included all subjects born in the country between 1896 and 1940 who were economically active in 1960-1.9 million men and 0.7 million women. Information on social and socio-economic status, and other social and demographic characteristics, was obtained from the 1960 Census. Information on cause-specific mortality during the period 1961-68 was obtained from a record linkage with the Cause of Death Registry. The analyses were based on 112,469 deaths and 21 million person years at risk. Information on smoking habits was obtained from a sample of 55,000 from the Census population. CHD mortality for women was high among manual workers, SMR = 110 (95% confidence limits 104-117), and low among non-manual workers, SMR = 84 (78-91). CNS-vascular mortality for women was also high among manual workers, SMR = 107 (110-115), and low among non-manual workers, SMR = 89 (82-97). Heavy smoking was more common among non-manual workers in both sexes, which may have contributed to a reverse social class gradient among men, with non-manual male workers being at higher risk for CHD than manual male workers. Farmers (and agricultural workers) generally had a low mortality. Other self-employed men and women had a high total mortality, a high mortality from CHD and CNS-vascular disease--and a high proportion of heavy smokers. There remain differences in mortality between social and socio-economic groups which cannot be explained by smoking habits, age, gender, urbanization, region of residence and martial status.

On some nonmonotone subdifferential boundary conditions in elastostatics

In the framework of linear elasticity some boundary conditions derived from nonconvex non-differentiable superpotentials are considered by making use of the notion of the generalized Clarke's gradient, [4, 5]. The existence of solutions to the corresponding boundary value problems, termed hemivariational inequalities (cf. [8–11]), is established. The method employed consists in finding the conditions sufficient for the generalized Clarke's gradient of a certain class of Lipschitz functions to be pseudo-monotone in the sense of F. E. Browder and P. Hess, [2]. The obtained results are applied to the investigation of a such problem in which the destruction of the support is taken into account.

Social inequalities in low birth weight: Timing of effects and selective mobility

The risk of giving birth to a low birth weight baby is known to be associated with poor material circumstances during the mother's own childhood. In addition to this long-term effect, an association is also apparent of low birth weight with the mother's current social class, measured in terms of her husband's occupation. At least two interpretations of this are possible: a true short-term effect, and/or selective social mobility (upward or downward). According to the latter hypothesis, social class at marriage reflects the operation of selective social processes such that taller and better educated women tend to marry men of higher social class: because both attributes are negatively associated with the risk of low birth weight, a short-term effect is mimicked. This paper investigates the strength of this effect, using data from a longitudinal study, the National Child Development Study. The possibility is also explored that the social class gradients at different ages are not independent: for example that a beneficial socio-economic environment in early life can compensate for hardship later on, in terms of the risk of low birth weight, and vice versa. A social class gradient was observed in the proportion of low birth weight deliveries, both at the time of the respondent's own birth and at the time of her marriage. Depending on the assumption made concerning the relationship of height with low birth weight, selective mobility for height explained 10.7% or 16.3% of the apparent short-term gradient in low birth weight. Selective mobility for educational level did not have any effect. Further analyses suggested that having belonged to a higher social class either in early childhood or at marriage had a beneficial effect, notwithstanding the direction of any mobility experienced. The social class of the woman's father when she was 16 was not associated with the low birth weight rate, and upward mobility during the respondent's childhood appeared to carry an increased risk.

Social class differences in infant mortality: the problem of competing hypotheses.

SummaryThere is no agreed explanation of the social class gradient in infant mortality. The longstanding debate continues between those who favour explanations based on natural or social selection and those who stress the influence of environmental circumstances. These explanations are often presented as competing hypotheses between which it is necessary to make an absolute choice. An article which takes this approach is critically examined. It is argued that such an approach may lead to erroneous conclusions, and may divert attention away from the primary task of understanding how to bring about further improvements in the survival of infants in the manual social classes.

A possible artefactual component in specific cause mortality gradients. Social class variations in the clinical accuracy of death certificates.

This paper investigates one possible avenue of artefactual influence on the production and/or concealment of social class gradients in specific cause mortality rates, namely, the possibility of social class biases in the accuracy of diagnosis of cause of death and the systematic misallocation of certain social groups to particular diagnoses. Information on this topic was obtained by matching occupational data gathered at death registration with data on the accuracy of diagnosis of cause of death (measured by diagnostic agreement between clinician and pathologist) collected in a prospective study of 1152 hospital necropsies. Extrapolation from these data to national mortality rates should be cautious, but it appears that in the majority of the most common causes of death grouped by ICD chapter (neoplasms, cerebrovascular and digestive) social class gradients would be steeper if mortality data were based on pathologists' rather than clinicians' diagnoses. Only in the respiratory chapter would the gradient be reduced, with the gradient in cardiovascular deaths unaffected.

Inequalities? Social class differentials in health in British youth

In the British context, there is a widespread assumption that inequalities in health between social classes are persistent feature of the life-course, an assumption appearing most plausible by reference to the more accessible published statistics on the issue. However, the age-bands typically employed are in fact so broad as to obscure important life-stages altogether. One such stage is youth which on the evidence of the major indicators of mortality, chronic illness and self-rated health is characterised more by the absence than presence of class gradients. That social class differentials re-emerge quite dramatically after this relative equalisation in youth has implications for the broader debate about the explanation of inequalities in health.

Social class, non-employment, and chronic illness: continuing the inequalities in health debate.

The 1981-2 General Household Survey showed steep class gradients in limiting longstanding illness for men and women aged 20-59 that were very similar to the class gradients in mortality in the 1979-83 decennial supplement. The class gradient for women classified by their husband's occupation was stronger than that when they were classified by their own occupation. Men and women who lacked paid employment reported poorer health than the employed and were concentrated in the lower social classes. Inequalities in ill health due to class were partly caused by the higher proportion in the lower social classes who were without work. Class differences in ill health still existed, however, among the currently employed, with unskilled men reporting particularly poor health and women manual workers reporting poorer health than women in non-manual jobs. Class differences were greater for the occupationless than for the currently employed. Thus class remains an important indicator of health inequalities despite the current high level of unemployment.

Cancers of affluence: Positive social class gradient and rising incidence trend in some cancer forms

This study shows that, unlike most diseases, some cancer forms are more common in upper social classes. All cancer cases diagnosed in Finland in 1971–1975 aged 30–69 and recorded in the Finnish Cancer Registry ( n=36,500) were linked to the file of the 1970 Population Census of Finland with data on socio-economic status and education. Cancers related to both high socio-economic status and high level of education in men were colon, prostate, testis, kidney and melanoma of the skin, and in women colon, breast, and corpus uteri. Since 1953, the incidence of all these cancers had been rising, although that of the testicular cancer had levelled off in the seventies.

Smoking attitudes and habits during pregnancy, Sheffield 1983

INTERVIEWS with 206 women post partum, as sessed their knowledge of the risks of smoking to pregnancy and general health, their sources of information and smoking habits during pregnancy. Thirty four per cent smoked at the beginning of pregnancy; 25 per cent quit and 44 per cent reduced consumption during pregnancy. Seventy five per cent of smokers remember receiving advice not to smoke during pregnancy, but the general practition er was cited by only 25 per cent. However advice, knowledge of the risks of smoking to health and a pregnancy, and partners' smoking habits were not associated with quitting or reducing consumption. There was a social class gradient in the proportion of smokers who were aware of the risks of smoking to health and pregnancy, but among non-smokers the higher all-round level of awareness was not in fluenced by social class. Although exposed to anti- smoking propaganda, smokers in Social Classes IV and V are unlikely to admit the risks of smoking and it remains unclear how best to motivate them to give up.

Health, health risks and inequalities: an exploratory study of women's perceptions.

Recent theoretical and empirical research has highlighted the importance of understanding the relationship between social structure and health beliefs. The empirical study described here explores the relationships between occupational social class and two dimensions of health beliefs which were concepts of health and perception of vulnerability to disease. Both the dimensions are claimed to be associated with decisions to carry out health behaviour and thus one of the aims was to shed some light on the social class gradient in patterns of preventive health behaviour and risk-taking behaviour. The findings showed a more marked social class differentiation in concepts of health when they were defined in the abstract compared with when they were defined in relation to personal health. The concept of personal vulnerability itself was shown to be problematic and theories about vulnerability were similar for both classes. Explanations for the findings are discussed.

The social distribution of illness: Is Australia more equal?

The relationship between socioeconomic status and ill health has challenged researchers and health practitioners for many years. This paper outlines the way several basic measures of morbidity are related to occupation, income and education, with brief attention to class gradients in mortality and service utilization. The international literature contains many studies showing an inverse gradient in health by social standing: people who are socially and economically well off typically enjoy good health as well. Data from a recent health survey conducted in New South Wales, Australia do not confirm the British findings when occupational categories are studied, but when other measures of status are substituted for the crude occupation categories, a number of patterns appear. Income is significantly associated with the probability of chronic illness among middle-aged men and women, and among women over 65. The predicted pattern is also evident for recent illness among young men and for consulting among elderly respondents, but these associations are not statistically significant. Except among the elderly, better educated men and women are healthier than those with less education on most morbidity measures. The parallels and discrepancies between these findings from an Australian sample and overseas studies raise important research and policy questions.

Selection and mortality differentials.

The Office of Population Censuses and Surveys Longitudinal Study provides reliable mortality data by a much wider range of characteristics than are available for other national sources. Although it is based on only a 1% sample of the population, it broadens the scope of mortality analysis and permits study of changes in relationships using different aspects of the time dimension. Data from this study have made us increasingly aware of the importance of selection to the interpretation and understanding of observed mortality differentials. Here we focus on that aspect of selection called "health-related mobility," which is associated with the relative health of people acquiring or losing individual characteristics. It is suggested that, for characteristics affected by health-related mobility, mortality differentials would narrow or widen with increased duration of follow-up. One of the basis of this argument the contribution of health-related mobility to mortality differentials by economic position and social class, to regional differentials, and to family and household differentials is investigated. Selection can thus be shown to operate when people change economic position, when they migrate, or when they change marital status. While the effects of these selection processes can be shown to contribute to social class gradients they do not explain regional differentials and contribute only to a limited degree to differentials by marital status. Differentials by household circumstances also reflect the product of selection processes.

Social class and psychological disorder in natives and immigrants to Britain.

An examination is made of various hypotheses which have been developed to account for the frequently observed inverse relationship between social class and psychological disturbance. Two of these explanations--the social selection and social causation hypotheses--are tested in a study designed to enable an assessment of their relative power to be made. Quasi-random samples of 200 Indian-born, 200 Pakistani-born and 240 native-born residents of England were interviewed and measures of social class, psychological symptoms and other relevant variables made. The results failed to support either of the two hypotheses as the expected social class gradient in psychological disorder only emerged in the native group. Indian immigrants in fact showed a reversal with higher status individuals, especially women, having higher symptom levels. Overall Indian immigrants had significantly fewer symptoms than either of the other groups. The findings are discussed in terms of differential selection for migration and the varying experiences of immigrants after arrival in Britain.

Convergence and divergence in regional patterns of infant mortality in the United Kingdom from 1949-51 to 1970-72.

Abstract Regional and social disparities in rates of infant mortality have recently been highlighted as a major source of concern. Social class gradients in infant mortality have been shown to have been persistent over the past few decades, despite the introduction of the National Health Service. Relatively little is known, however, about the persistence or otherwise of geographical gradients in infant mortality. This paper describes the relative change in infant mortality in the United Kingdom by local authority areas between 1949–1951 and 1970–1972, using a typology of change derived from the results of a linear regression analysis. It is shown that the overall intensity of spatial inequality has changed very little over the period. At the same time, however, the relative position of some areas has deteriorated significantly, while that of others has significantly improved.