Infant Mortality Rate as a Measure of a Country’s Health: A Robust Method to Improve Reliability and Comparability

Researchers and policymakers often rely on the infant mortality rate as an indicator of a country’s health. Despite arguments about its relevance, uniform measurement of infant mortality is necessary to guarantee its use as a valid measure of population health. Using important socioeconomic indicators, we develop a novel method to adjust country-specific reported infant mortality figures. We conclude that an augmented measure of mortality that includes both infant and late fetal deaths should be considered when assessing levels of social welfare in a country. In addition, mortality statistics that exhibit a substantially high ratio of late fetal to early neonatal deaths should be more closely scrutinized.     

High-risk families: the unequal distribution of infant mortality in nineteenth-century Sweden

An analysis of infant mortality (based on 133,448 births) in two regions, Sundsvall and Skellefte?, in north-eastern Sweden during the nineteenth century shows that infant mortality was highly clustered with a relatively small number of families accounting for a large proportion of all infant deaths. Using logistic regression, two important factors were found to be associated with high-risk families: (i) a biological component evidenced by an over-representation of women who had experienced stillbirths, and (ii) a social component indicated by an increased risk among women who had remarried. The results strengthen the argument for using the family rather than the single child as the unit of analysis. The clustering of infant deaths points to the need to re-evaluate our interpretations of the causes of infant mortality in the past.     

Death and Taxes: Longer life, consumption, and social security

We analyze in three steps the influence of the projected mortality decline on the long run finances of the Social Security System. First, on a theoretical level, mortality decline adds person years of life which are distributed across the life cycle. The interaction of this distribution with the age distribution of labor earnings minus consumption, or of taxes minus benefits, partially determines the corresponding steady state financial consequences of mortality decline. The effect of mortality decline on population growth rates also matters, but is negligible in low mortality populations. Second, examination of past mortality trends in the United States and of international trends in low mortality populations, suggests that mortality will decline faster than foreseen by the Social Security Administration s forecasts. Third, we combine the work of the first two parts in dynamic simulations to examine the implications of mortality decline and of alternative forecasts of mortality for the finances of the social security system. Also, we use stochastic population forecasts to assess the influence of uncertainty about mortality decline on uncertainty about finances; we find that uncertainty about fertility still has more important implications than uncertainty about mortality, contrary to sensitivity tests in the official forecasts.     

Structural and Cognitive Aspects of Social Capital and All-Cause Mortality: A Meta-Analysis of Cohort Studies

Social capital covers different characteristics such as social networks, social participation, social support and trust. The aim of this study was to explore which aspects of social capital were predictive of mortality. Criteria for inclusion in the meta-analysis were: population based observational cohort studies (follow-up ≥5 years); study sample included the adult population; parts of social capital as the primary exposure variable of interest; reported a mortality outcome; and sample size >1,000 individuals. Twenty studies provided eligible data for the meta-analyses. A random effect model was used to estimate the combined overall hazard rate ratio effects of structural social capital such as social participation and social networks, and cognitive social capital including social support and trust in relation to mortality. The results showed that social participation and social networks were negatively associated with mortality. The impact of social networks attenuated somewhat when controlling for gender and age. While trust also appeared to be negatively associated with mortality, we remain cautious with this conclusion, since only two studies provided eligible data. Perceived social support failed to show a significant impact upon mortality. The findings suggest that people who engage socially and report frequent contacts with friends and family live longer.     

Polygynous Contexts,Family Structure,and Infant Mortality in Sub-Saharan Africa

Contextual characteristics influence infant mortality above and beyond family-level factors. The widespread practice of polygyny is one feature of many sub-Saharan African contexts that may be relevant to understanding patterns of infant mortality. Building on evidence that the prevalence of polygyny reflects broader economic, social, and cultural features and that it has implications for how families engage in the practice, we investigate whether and how the prevalence of polygyny (1) spills over to elevate infant mortality for all families, and (2) conditions the survival disadvantage for children living in polygynous families (i.e., compared with monogamous families). We use data from Demographic and Health Surveys to estimate multilevel hazard models that identify associations between infant mortality and region-level prevalence of polygyny for 236,336 children in 260 subnational regions across 29 sub-Saharan African countries. We find little evidence that the prevalence of polygyny influences mortality for infants in nonpolygynous households net of region-level socioeconomic factors and gender inequality. However, the prevalence of polygyny significantly amplifies the survival disadvantage for infants in polygynous families. Our findings demonstrate that considering the broader marital context reveals important insights into the relationship between family structure and child well-being.     

Health,wartime stress,and unit cohesion: Evidence from Union Army veterans

We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.     

The impact of class,education, and health care on infant mortality in a developing society: The case of rural Thailand

Demographic and social factors affecting infant mortality in rural northern Thailand are examined using log-linear modifiedmultiple regression models and data drawn from a representative sample of married couples in Chiang Mai and Chiang Rai provinces. Demographic factors do not account for the effects of variations in parental ability or willingness to provide adequate infant care. The final model estimated incorporated both these social dimensions of child care. Parental ability, measured by father’s social class, mother’s health information, and local community development levels, continued to have significant independent effects upon infant survival. Parental willingness, measured by parent’s beliefs about intergenerational wealth transfers, no longer had a significant effect net of other social variables, but infant survival was still affected by whether both parents wanted a birth.     

Social networks and HIV/AIDS risk perceptions

Understanding the determinants of individuals' perceptions of their risk of becoming infected with HIV and their perceptions of acceptable strategies of prevention is an essential step toward curtailing the spread of this disease. We focus in this article on learning and decision-making about AIDS in the context of high uncertainty about the disease and appropriate behavioral responses. We argue that social interactions are important for both. Using longitudinal survey data from rural Kenya and Malawi, we test this hypothesis. We investigate whether social interactions--and especially the extent to which social network partners perceive themselves to be at risk--exert causal influences on respondents' risk perceptions and on one approach to prevention, spousal communication about the threat of AIDS to the couple and their children. The study explicitly allows for the possibility that important characteristics, such as unobserved preferences or community characteristics, determine not only the outcomes of interest but also the size and composition of networks. The most important empirical result is that social networks have significant and substantial effects on risk perceptions and the adoption of new behaviors even after we control for unobserved factors.     

Socialist system creates favourable social environment for fertility decline in China

The Chinese experience suggests that the socialist system can create more favorable conditions for a decline in fertility than the capitalist system. This is related to 5 factors: 1) changes in the traditional functions of the nuclear family; 2) popularization of education and the transmission of culture; 3) improvements in the status of women; 4) rapid decreases in mortality, especially infant mortality; and 5) social security for the aged. In addition, the structure of social organizations and the widespread dissemination of information about birth control methods have facilitated family planning practice. The impact of theswe structural factors has been intensfied by the Chinese social environment, which has changed individual attitudes toward family size. Overall, the social environment has created attitudinal change while implementaton of the national family planning policy has made the fertility decline in China possible.     

The cost of uncertain life span

Much uncertainty surrounds the length of human life. The standard deviation in adult life span is about 15 years in the USA, and theory and evidence suggest that it is costly. I calibrate a utility-theoretic model that shows that 1 year in standard deviation is worth about half a life year. Differences in variance exacerbate health inequalities between and among rich and poor countries. Accounting for the cost of life-span variance appears to amplify recently discovered patterns of convergence in world average human well-being because the component of variance due to infant mortality has exhibited even more convergence than life expectancy.     

Erosion of Advantage: Decomposing Differences in Infant Mortality Rates Among Older Non-Hispanic White and Mexican-Origin Mothers

We build on findings from recent research showing an erosion of infant survival advantage in the Mexican-origin population relative to non-Hispanic whites at older maternal ages, with patterns that differ by nativity. This runs counter to the well-documented Hispanic infant mortality paradox and suggests that weathering and/or other negative health selection mechanisms may contribute to increasing disadvantage at older maternal ages. Using the National Center for Health Statistics (NCHS) cohort-linked birth and infant death files, we decompose the difference in Mexican-origin non-Hispanic white infant mortality at older maternal ages to better understand the contribution of selected medical and social risk factors to components of the difference. We find differences in the distribution and effects of risk factors across the three populations of interest. The infant mortality rate (IMR) gap between Mexican-origin women and non-Hispanic whites can be attributed to numerous offsetting factors, with inadequate prenatal care standing out as a major contributor to the IMR difference. Equalizing access to and utilization of prenatal care may provide one possible route to closing the IMR gap at older maternal ages.     

Mortality in Ghana: Evidence from the cape coast project data

Abstract This paper deals with the estimation of mortality for a rural community of about 20,000 persons in the rain-forest area of south-west Ghana. Specifically, infant, child and adult mortality estimates have been obtained by the application of a wide range of direct and indirect methods of measuring mortality from the different statistics collected by a longitudinal mortality and fertility project conducted during 1974-7. It was noted that infant and childhood mortality rates obtained from death registrations were consistent with those rates yielded by pregnancy histories and child survival statistics. However, the adult mortality estimates derived from orphanhood statistics tended to be lower than those suggested by death registrations. The analysis revealed an infant mortality rate of 100 for boys and 84 for girls, equal childhood mortality rates for boys and girls (85-6), a lower expectation of life at birth for men (45.8 years) than for women (52.8), and a much more severe incidence of mortality among men aged over 40 than for women at the corresponding ages.     

Mortality in Ghana: Evidence from the cape coast project data

This paper deals with the estimation of mortality for a rural community of about 20,000 persons in the rain-forest area of south-west Ghana. Specifically, infant, child and adult mortality estimates have been obtained by the application of a wide range of direct and indirect methods of measuring mortality from the different statistics collected by a longitudinal mortality and fertility project conducted during 1974–7. It was noted that infant and childhood mortality rates obtained from death registrations were consistent with those rates yielded by pregnancy histories and child survival statistics. However, the adult mortality estimates derived from orphanhood statistics tended to be lower than those suggested by death registrations. The analysis revealed an infant mortality rate of 100 for boys and 84 for girls, equal childhood mortality rates for boys and girls (85–6), a lower expectation of life at birth for men (45.8 years) than for women (52.8), and a much more severe incidence of mortality among men aged over 40 than for women at the corresponding ages.     

Breast feeding, fertility and infant mortality: An analysis of some early German data

Abstract Concern about high infant mortality and its suspected connection with the lack of breast-feeding stimulated the collection of statistics about the frequency of breast-feeding in several German states during the late roth and early 20th centuries. Contrary to the assumption that universal and extended breast-feeding is customary among rural agricultural populations, large regional variations existed both in the proportion of children who were breast-fed and in the average duration of the period for which they were breast-fed. An analysis of these data in connection with statistics of infant mortality and marital fertility confirms the association between high infant mortality and the absence of breast-feeding. An hypothesis linking breast-feeding and fertility, however, is not confirmed. Marital fertility appears to be much more closely associated with infant mortality than with breast-feeding.     

The Level and Age Pattern of Mortality in Bandafassi (Eastern Senegal): Results From a Small-Scale and Intensive Multi-Round Survey

The data collected in the Bandafassi demographic study in Eastern Senegal, a small-scale intensive and experimental follow-up survey of a population of about 7,000 in 1983, were analysed to derive an estimated life table. The use of multi-round surveys, combined with anthropological methods to estimate ages and collect genealogies, has resulted in unusually reliable data. Taking into account the uncertainty of the estimates due to the small size of the population, mortality was high, with life-expectancy at birth close to 31 years; a pattern of infant and child mortality close to that observed in other rural areas of Senegal, with a very high level or mortality between ages six months and three years; a seasonal pattern in child mortality with two high-risk periods, the rainy season and the end of the dry season; an adult mortality pattern similar to that described in model life tables for developed countries; no significant difference by sex or ethnic group. The Bandafassi population study and a few similar studies suggest that one possible way to improve demographic estimates in countries where vital registration systems are defective would be to set up a sample of population laboratories where intensive methods of data collection would continue for extended periods.     

Breast feeding,fertility and infant mortality: An analysis of some early German data

Concern about high infant mortality and its suspected connection with the lack of breast-feeding stimulated the collection of statistics about the frequency of breast-feeding in several German states during the late roth and early 20th centuries. Contrary to the assumption that universal and extended breast-feeding is customary among rural agricultural populations, large regional variations existed both in the proportion of children who were breast-fed and in the average duration of the period for which they were breast-fed. An analysis of these data in connection with statistics of infant mortality and marital fertility confirms the association between high infant mortality and the absence of breast-feeding. An hypothesis linking breast-feeding and fertility, however, is not confirmed. Marital fertility appears to be much more closely associated with infant mortality than with breast-feeding.     

The linked survival prospects of siblings: evidence for the Indian states

This paper reports an analysis of micro-data for India that shows a high correlation in infant mortality among siblings. In 13 of 15 states, we identify a causal effect of infant death on the risk of infant death of the subsequent sibling (a scarring effect), after controlling for mother-level heterogeneity. The scarring effects are large, the only other covariate with a similarly large effect being mother's (secondary or higher) education. The two states in which evidence of scarring is weak are Punjab, the richest, and Kerala, the socially most progressive. The size of the scarring effect depends upon the sex of the previous child in three states, in a direction consistent with son-preference. Evidence of scarring implies that policies targeted at reducing infant mortality will have social multiplier effects by helping avoid the death of subsequent siblings. Comparison of other covariate effects across the states offers some interesting new insights.     

The linked survival prospects of siblings: Evidence for the Indian states

This paper reports an analysis of micro-data for India that shows a high correlation in infant mortality among siblings. In 13 of 15 states, we identify a causal effect of infant death on the risk of infant death of the subsequent sibling (a scarring effect), after controlling for mother-level heterogeneity. The scarring effects are large, the only other covariate with a similarly large effect being mother's (secondary or higher) education. The two states in which evidence of scarring is weak are Punjab, the richest, and Kerala, the socially most progressive. The size of the scarring effect depends upon the sex of the previous child in three states, in a direction consistent with son-preference. Evidence of scarring implies that policies targeted at reducing infant mortality will have social multiplier effects by helping avoid the death of subsequent siblings. Comparison of other covariate effects across the states offers some interesting new insights.     

The increasing racial disparity in infant mortality: Respiratory distress syndrome and other causes

Although substantial declines in infant mortality rates have occurred across racial/ethnic groups, there has been a marked increase in relative black-white disparity in the risk of infant death over the past two decades. The objective of our analysis was to gain insight into the reasons for this growing inequality on the basis of data from linked cohort files for 1989-1990 and 1995-1998. We found a nationwide reversal from a survival advantage to a survival disadvantage for blacks with respect to respiratory distress syndrome over this period. The results are consistent with the view that the potential for a widening of the relative racial gap in infant mortality is high when innovations in health care occur in a continuing context of social inequality. As expected, the results for other causes of infant mortality, although similar, are less striking. Models of absolute change demonstrate that among low-weight births, absolute declines in mortality were greater for white infants than for black infants.     

Determinants of temporal and areal variation in infant mortality in Germany, 1871–1933

This article investigates how sociodemographic, economic, medical, and public health factors influence infant mortality by using data about German administrative areas from 1871 to 1933. Marital fertility has the largest impact on infant mortality, followed by illegitimacy, medical care, urbanization, and infant welfare centers. The variables considered here account for most of the variation in infant mortality. Some of the unexplained variance is due to factors associated with regions, such as breastfeeding patterns, and with time periods, such as national health insurance. The analyses found no evidence that advances in medical technology affected infant mortality or that the influence of economic development changed over time.