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Objective Studies on child malnutrition find no evidence of gender difference in childhood stunting (48% for both boys and girls) in India. Several States show a better nutritional status of girls than boys. Therefore, we argued that in an environment of high mortality among girls, the surviving girls are highly wanted and thus are healthier. Therefore, child nutritional status cannot be studied independent of mortality. Methods We used three rounds of data from the National Family Health Survey 1992-93,1998-99,2015-16 to examine whether Indian girls are really better nourished than boys. Height for age z-score (HAZ), as defined by the World Health Organization was used to measure the health of children. We first imputed the HAZ for dead boys and girls using multiple imputation techniques. Second, these imputed HAZ for dead boys and girls were combined with HAZ of surviving boys and girls to provide a simulated HAZ separately for boys and girls. Results Results show that relative reduction in average HAZ was slightly higher for girls than boys in each of three rounds of NFHS. Although the relative decline in average HAZ was higher for girls than boys, the simulated z-scores after incorporating the average HAZ for dead children suggest no significant difference between the overall HAZ of boys and girls in any of the three surveys. Conclusion We do not find enough evidence to establish the effect of mortality selection in explaining the better nutritional status of girls compared with boys in India. Our findings are consistent across the three rounds of NFHS and at different levels of mortality.

By the end of spring (31 May), the COVID-19 death rate was remarkably unevenly distributed across the countries in Europe. While the risk of COVID-19 mortality is known to increase with age, age-specific COVID-19 death rates across Europe were similarly unevenly distributed. To explain these mortality distributions, we present a simple model where more favorable survival environments promote longevity and the accumulation of health frailty among the elderly while less favorable survival environments induce a mortality selection process that results in lower health frailty. Because the age-related conditions of frailty render the elderly less resistant to SARS-CoV-2, pre-existing survival environments may be non-obviously positively related to the COVID-19 death rate. To quantify the survival environment parameter of our model, we leveraged historic cohort- and period-based age-specific probabilities of death and life expectancies at age 65 across Europe. All variables are significantly correlated with indicators of frailty like elderly dependence on others for personal and household care for a subset of European countries. With respect to COVID-19 death rates, we find significant positive relationships between our survival indicators and COVID-19 death rates across Europe, a result that is robust to statistical control for the capacity of a healthcare system to treat and survive infected persons, the timing and stringency of non-pharmaceutical interventions, population density, age structure, case rates and the volume of inbound international travelers, among other factors. To address possible concerns over reporting heterogeneity across countries, we show that results are robust to the substitution of our response variable for a measure of cumulative excess mortality. Also consistent with the intuition of our model, we also show a strong negative association between age-specific COVID-19 death rates and pre-existing all-cause age-specific mortality rates for a subset of European countries. Overall, results support the notion that variation in pre-existing frailty, resulting from heterogeneous survival environments, partially accounts for striking differences in COVID-19 death during the first wave of the pandemic.

Theoretical models of mortality selection have great utility in explaining otherwise puzzling phenomena. The most famous example may be the Black-White mortality crossover: at old ages, Blacks outlive Whites, presumably because few frail Blacks survive to old ages while some frail Whites do. Yet theoretical models of unidimensional heterogeneity, or frailty, do not speak to the most common empirical situation for mortality researchers: the case in which some important population heterogeneity is observed and some is not. I show that, when one dimension of heterogeneity is observed and another is unobserved, neither the observed nor the unobserved dimension need behave as classic frailty models predict. For example, in a multidimensional model, mortality selection can increase the proportion of survivors who are disadvantaged, or “frail,” and can lead Black survivors to be more frail than Whites, along some dimensions of disadvantage. Transferring theoretical results about unidimensional heterogeneity to settings with both observed and unobserved heterogeneity produces misleading inferences about mortality disparities. The unusually flexible behavior of individual dimensions of multidimensional heterogeneity creates previously unrecognized challenges for empirically testing selection models of disparities, such as models of mortality crossovers.

This study uses the micro-simulation method to investigate the role of cohort forces in age-dependent mortality pattern. We test the micro mechanisms for cohort evolution and mortality selection, and how these two biological and demographic forces may interact with epidemiologic transition to shape the cohort age-dependence of mortality pattern in both early- and later-transition countries. We show that cohort evolution is due to the declining rate of mortality acceleration at the individual level, which is associated with lower initial mortality rates but not smaller variance of frailty distribution in later birth cohorts. The steeper slope of mortality acceleration at the population level among later birth cohorts is due to mortality selection mechanism associated with smaller variance of frailty distribution but not lower initial mortality rates. These two forces jointly shape the non-crossover cohort age-dependence of mortality pattern regardless of the differential mechanisms of epidemiologic transition in early- and later-transition countries.

About 200 million children globally are not meeting their growth potential, and as a result will suffer the consequences in terms of future outcomes. I examine the effects of birth weight on child health and growth using information from 66 countries. I account for missing data and measurement error using instrumental variables and adopt an identification strategy based on siblings and twins. I find a consistent effect of birth weight on mortality risk, stunting, wasting, and coughing, with some evidence for fever, diarrhoea, and anaemia. Bounds analysis indicates that coefficients may be substantially underestimated due to mortality selection. Improving the pre-natal environment is likely to be important for helping children reach their full potential.

OBJECTIVES: Age- and sex-specific rates of dementia are estimated in the U.S. population aged 65 or older in 2000 and 2012 using a large nationally representative dataset, the Health and Retirement Study (HRS), and accounting for mortality selection and specificities of the interview protocol. METHOD: A latent cognitive ability model is estimated by maximum simulated likelihood. Prevalence of dementia is identified using HRS cognition measures and the Aging, Demographics and Memory Study (ADAMS), a subset of the HRS (n = 856) with clinical assessment for dementia. Different cognitive measures are collected in self and proxy interviews. From 2006 onward, the HRS collected fewer interviews by proxy. Selection into proxy interviews is modeled as well as survival into the ADAMS sample from the previous HRS interview. RESULTS: The prevalence of dementia decreased from 12.0% (SE = 0.48%) in 2000 to 10.5% (SE = 0.49%) in 2012 in the 65+ population, a statistically significant decline of 12.6% (p < .01). The percentage change in prevalence was larger among males (16.6% vs 9.5%), and younger individuals. DISCUSSION: The prevalence of dementia among those 65 or older decreased between 2000 and 2012, although less rapidly than reported in other studies. The difference is primarily due to our modeling selection into proxy interviews.

A reduced survival as a potential cost of high lifetime reproductive effort in women has intrigued human evolutionary biologists for more than a century. However, we do not currently have compelling evidence for the delayed survival costs of reproduction. Reasons for this may include several methodological issues, such as environmental confounding, measurement of individuals' lifetime reproductive effort using demographic data, and the practice of mortality selection that are all likely to compromise our ability to reliably detect trade-offs at the phenotypic level. The current research aims to address all these issues by using structural equation modeling to examine the potential trade-off between women's lifetime reproductive effort and their postreproductive mortality in a large data set of 6,594 women from preindustrial northern Sweden that has not previously been used for this purpose. Despite this, the results showed only weak evidence for a trade-off between lifetime reproductive effort and postreproductive mortality, one that was confined to only those women who had high lifetime reproductive effort and spend more than 25 years in widowhood. The socioeconomic status of the family or mother's ethnic background did not moderate this association, with the general trend being one of higher, not lower, postreproductive survival with high lifetime reproductive effort in women.

Exposure to extreme events has been hypothesized to affect subsequent mortality because of mortality selection and scarring effects of the event itself. We examine survival at and in the five years after the 2004 Indian Ocean earthquake and tsunami for a population-representative sample of residents of Aceh, Indonesia who were differentially exposed to the disaster. For this population, the dynamics of selection and scarring are a complex function of the degree of tsunami impact in the community, the nature of individual exposures, age at exposure, and gender. Among individuals from tsunami-affected communities we find evidence for positive mortality selection among older individuals, with stronger effects for males than for females, and that this selection dominates any scarring impact of stressful exposures that elevate mortality. Among individuals from other communities, where mortality selection does not play a role, there is evidence of scarring with property loss associated with elevated mortality risks in the five years after the disaster among adults age 50 or older at the time of the disaster.

This research investigates long-term consequences of early-life malnutrition by examining effects of the 1959-1961 Chinese Famine. Taking into account temporal and geographic variations in famine severity, we construct a difference-in-differences estimator to identify effects of early-life exposure to famine on perceived health and socioeconomic outcomes in midlife. Using a sample of 1716 adults born in 1955-1966 in rural China from a nationally representative survey-the 2005 Chinese General Social Survey-we find that the famine had adverse effects on mid-life health for males born into families where at least one parent was a Communist Party member and females regardless of parental party membership. Being born during the famine had no effects on years of education or income for either gender. Quantile regressions suggest intense mortality selection among males who had no party-affiliated parents. Our study highlights the importance of timing and contexts of life experiences in shaping health.

Background: The impact of extreme conditions on survival has been the focus of mortality studies using military data. However, in countries at peace, the military live in favorable conditions, being positively selected with respect to health. In this type of context, military data may help to improve our understanding of mortality differentials, particularly in countries where defective vital systems are still cumbersome for mortality studies. Methods: We estimate death rates for Brazilian Air Force (BAF) officers through Poisson regression models, compute life expectancies, and compare them with those of average Brazilians and people in low-mortality countries. We also examine causes of death and mortality differentials through a competing risks framework and Fine and Gray regression models. Results: BAF life expectancy is higher than that of the average Brazilian and comparable to Sweden, France, and Japan in 2000. Younger pilots have a higher risk of dying on duty when compared with other officers but experience lower mortality rates from other causes at advanced ages. Conclusions: BAF officers are a population subgroup in Brazil with a life expectancy comparable to the one in advanced societies. There is no association between mortality and place of birth, which indicates that different childhood backgrounds did not affect BAF mortality differentials later in life. Contribution: This paper takes a novel approach focusing on a specific subgroup with lower mortality rates than the general population and good-quality longitudinal information available, a rarity in developing countries. We argue that this approach can be an interesting strategy to study mortality differentials in developing countries.

Mortality selection is a general concern in the social and health sciences. Recently, existing health and social science cohorts have begun to collect genomic data. Causes of selection into a genomic dataset can influence results from genomic analyses. Selective non-participation, which is specific to a particular study and its participants, has received attention in the literature. But mortality selection—the very general phenomenon that genomic data collected at a particular age represents selective participation by only the subset of birth cohort members who have survived to the time of data collection—has been largely ignored. Here we test the hypothesis that such mortality selection may significantly alter estimates in polygenetic association studies of both health and non-health traits. We demonstrate mortality selection into genome-wide SNP data collection at older ages using the U.S.-based Health and Retirement Study (HRS). We then model the selection process. Finally, we test whether mortality selection alters estimates from genetic association studies. We find evidence for mortality selection. Healthier and more socioeconomically advantaged individuals are more likely to survive to be eligible to participate in the genetic sample of the HRS. Mortality selection leads to modest drift in estimating time-varying genetic effects, a drift that is enhanced when estimates are produced from data that has additional mortality selection. There is no general solution for correcting for mortality selection in a birth cohort prior to entry into a longitudinal study. We illustrate how genetic association studies using HRS data can adjust for mortality selection from study entry to time of genetic data collection by including probability weights that account for mortality selection. Mortality selection should be investigated more broadly in genetically-informed samples from other cohort studies.

Unobserved heterogeneity in mortality risk is pervasive and consequential. Mortality deceleration—the slowing of mortality’s rise with age—has been considered an important window into heterogeneity that otherwise might be impossible to explore. In this article, I argue that deceleration patterns may reveal surprisingly little about the heterogeneity that putatively produces them. I show that even in a very simple model—one that is composed of just two subpopulations with Gompertz mortality—(1) aggregate mortality can decelerate even while a majority of the cohort is frail; (2) multiple decelerations are possible; and (3) mortality selection can produce acceleration as well as deceleration. Simulations show that these patterns are plausible in model cohorts that in the aggregate resemble cohorts in the Human Mortality Database. I argue that these results challenge some conventional heuristics for understanding the relationship between selection and deceleration; undermine certain inferences from deceleration timing to patterns of social inequality; and imply that standard parametric models, assumed to plateau at most once, may sometimes badly misestimate deceleration timing—even by decades.

Exposure to extreme events has been hypothesized to affect subsequent mortality because of mortality selection and scarring effects of the event itself. We examine survival at and in the five years after the 2004 Indian Ocean earthquake and tsunami for a population-representative sample of residents of Aceh, Indonesia who were differentially exposed to the disaster. For this population, the dynamics of selection and scarring are a complex function of the degree of tsunami impact in the community, the nature of individual exposures, age at exposure, and gender. Among individuals from tsunami-affected communities we find evidence for positive mortality selection among older individuals, with stronger effects for males than for females, and no evidence of scarring. Among individuals from other communities, property loss is associated with elevated mortality risks in the five years after the disaster only for those who were age 50 or older at the time of the disaster.

When investigating relationships between education and health, one has to take age into account. Conditioning on age entails conditioning on surviving, which has been argued to lead to a potential selection bias. In this note, I argue that surviving should be considered as a necessary precondition for the relationships of interest and, therefore, not as a possible source of bias. I criticize models of health trajectories that do not condition on surviving.

The system of full mobilisation and the modest effects of the World War II events on the civil population make Finland a highly useful case for exploring whether war veterans have elevated long-term mortality risks. Using data from the Human Mortality Database and a register-based micro sample with main causes of death, we study men in the cohorts who participated in the wars against the Soviet Union in 1939–1944. For these war cohorts, we find no indications of reduced survival after the early 1950s, as compared with male cohorts without combat experience. The absence of a long-term effect might be an artefact of mortality selection. In the first few years after war-end, death rates remained relatively high because of infectious diseases that killed off the weakest of the survivors. The results are in line with a series of other studies and illustrate that in the potential presence of cohort inversion there are no visible long-term effects of war experience on later-life survival.

Age of tooth emergence is a useful measure of the pace of life for primate species, both living and extinct. A recent study combining wild chimpanzees of the Tai Forest, Gombe, and Bossou by Zihlman et al. (2004) suggested that wild chimpanzees erupt teeth much later than captives, bringing into question both comparisons within the hominin fossil record and assessment of chimpanzees. Here, we assess the magnitude of the “wild effect” (the mean difference between captive and wild samples expressed in standard deviation units) in these chimpanzees. Tooth emergence in these wild individuals is late, although at a more moderate level than previously recorded, with a mean delay conservatively estimated at about 1 SD compared to the captive distributions. The effect rises to 1.3 SD if we relax criteria for age estimates. We estimate that the mandibular M1 of these wild chimpanzees emerges at about 3 2/3–3 ¾ years of age. An important point, often ignored, is that these chimpanzees are largely dead of natural causes, merging the effect of living wild with the effect of early death. Evidence of mortality selection includes, specifically: younger deaths appear to have been more delayed than the older in tooth emergence, more often showed evidence of disease or debilitation, and revealed a higher occurrence of dental anomalies. Notably, delay in tooth emergence for live-captured wild baboons appears lower in magnitude (ca. 0.5 SD) and differs in pattern. Definitive ages of tooth emergence times in living wild chimpanzees must be established from the study of living animals. The fossil record, of course, consists of many dead juveniles; the present study has implications for how we evaluate them.

Evidence shows that exposure to nutritional adversity in early life has larger long-term impacts on women than on men. Consistent with these findings, our paper shows a higher incidence of disability and illiteracy among female survivors of the Great Chinese Famine (1959-1961). Moreover we find that the better health of male survivors most plausibly reflects higher male excess mortality during the famine, whereas the observed gender difference in illiteracy rate is probably better explained by the culture of son preference.

Objectives. Although research on health limitations has investigated gender differences in health and mortality gender differentials in individual-level trajectories have been studied less frequently Moreover, there are no studies on the relationship between course types and subsequent mortality We investigate course types. explore confounding by socioeconomic and demographic correlates. and pose the question of whether the gender gap in morbidity results from differences in the onset of, and/or survival with, health limitations Method. Using the German Socioeconomic Panel, we identify Individual trajectories Ill health limitations and use multinomial logistic regressions to explore confounding and the relationship with mortality Results The frequency of stable trajectories without limitations is lower among women because they tend to experience courses that involve extended periods of limitations and deteriorating health Women at so experience more frequently improvement after deterioration The female mortality advantage is particularly huge alter health deterioration Discussion. Health limitations do not make men and women more equal in the lace of death Our results are consistent with earlier studies showing that mortality selection and differences in chronic conditions may explain the gender gap in health and mortality We extend previous research showing that the female health disadvantage is largely the result of their mortality advantage

The impact of SES on mortality is an established finding in mortality research. I examine, whether this impact decreases with age. Most research finds evidence for this decrease but it is unknown whether the decline is due to mortality selection. My data come from the US-HRS Study and includes 9376 persons aged 59+, which are followed over 8 years. The variables allow a time varying measurement of SES, health and behavior. Event-history-analysis is applied to analyze mortality differentials. My results show that socioeconomic mortality differences are stable across ages whereas they decline clearly with decreasing health. The first finding that health rather than age is the equalizer combined with the second finding of unequally distributed health leads to the conclusion that in old age, the impact of SES is transferred to health and is stable across ages.

Whether a cost of reproduction exists among humans is still questionable. A major study of aristocratic British families finds a significant positive correlation between parity and late-life mortality, which indicates a trade-off between reproduction and longevity. This result is supported by four other studies, while earlier studies have not found a relationship or came to the opposite conclusion. We show that in natural fertility populations the relationship between fertility and late-life mortality cannot be studied correctly without considering the effects of differences in health and of mortality selection during childbearing ages because these two effects lead to a dampening of the true relationship. If these effects are controlled in Hollingsworth's genealogy of the British peerage a significant trade-off between reproduction and longevity exists for females but not for males.

The aim is to describe the pattern of survival to old ages and the level of mortality selection for the centenarians in the five countries, using standard demographic indicators (i.e., life expectancy, mortality rates and probability to survive to specific ages) and more recently developed longevity indicators (i.e., modal age at death (M), mean deviation at M and centenarian rates). Under the current mortality conditions (years 2010–2012), 6% percent of the female newborn will become centenarian in Japan versus 4% in France and 2% in Denmark and in Sweden. The respective figures for male newborn are 1.4%, 1.1% and 0.6%. As expected the five low mortality selected countries for the 5-COOP study offer a variety of mortality selection for the surviving centenarian which will allow testing possible trade-off between longevity and functioning.

Background: A number of studies have examined the influence of life conditions in infancy (and pregnancy) on mortality risks in adulthood or old age. For those individuals who survived difficult life conditions, some scholars have found a prevalence of positive selection (relatively low mortality within the population), while others have observed the prevalence of a so-called scar-effect (relatively high mortality within the population). Objective: Using micro-data characterized by broad internal mortality differences before the demographic transition (seven parishes within the region of Veneto, North-East Italy, 1816-35), we aim to understand whether children who survived high mortality risks during the first three months of life (early infant mortality) had a higher or a lower probability of surviving during the following 33 months (late infant mortality). Methods: Using a Cox regression, we model the risk of dying during the period of 3-35 months of age, considering mortality level survived at age 0-2 months of age as the main explanatory variable. Results: We show that positive selection prevailed. For cohorts who survived very severe early mortality selection (q0-2>400‰, , where the subscripts are months of age), mortality hazard of death during the following 33 months was 20Š-30Š lower compared to the cohorts where early mortality selection was relatively small (q0-2Conclusions: This result points to a homeostatic mechanism: mortality variability among the cohorts is, for q0-35, half that of the mortality variability for both q0-2 and q3-35. Comments: old title: Neonatal selection and mortality in the following months of life

The gradual changes in cohort composition that occur as a result of selective mortality processes are of interest to all aging research. We present the first illustration of changes in the distribution of specific cohort characteristics that arise purely as a result of selective mortality. We use data on health, wealth, education, and other covariates from two cohorts (the AHEAD cohort, born 1900–1923 and the HRS cohort, born 1931–1941) included in the Health and Retirement Survey, a nationally representative panel study of older Americans spanning nearly two decades (N = 14,466). We calculate sample statistics for the surviving cohort at each wave. Repeatedly using only baseline information for these calculations so that there are no changes at the individual level (what changes is the set of surviving respondents at each specific wave), we obtain a demonstration of the impact of mortality selection on the cohort characteristics. We find substantial changes in the distribution of all examined characteristics across the nine survey waves. For instance, the median wealth increases from about $90,000 to $130,000 and the number of chronic conditions declines from 1.5 to 1 in the AHEAD cohort. We discuss factors that influence the rate of change in various characteristics. The mortality selection process changes the composition of older cohorts considerably, such that researchers focusing on the oldest old need to be aware of the highly select groups they are observing, and interpret their conclusions accordingly.

Blacks experience morbidity and mortality earlier in the life course compared to whites. Such premature declines in health may be indicative of an acceleration of the aging process. The current study uses data on 7,644 black and white participants, ages 30 and above, from the third National Health and Nutrition Examination Survey, to compare the biological ages of blacks and whites as indicated from a combination of ten biomarkers and to determine if such differences in biological age relative to chronological age account for racial disparities in mortality. At a specified chronological age, blacks are approximately 3 years older biologically than whites. Differences in biological age between blacks and whites appear to increase up until ages 60-65 and then decline, presumably due to mortality selection. Finally, differences in biological age were found to completely account for higher levels of all-cause, cardiovascular and cancer mortality among blacks. Overall, these results suggest that being black is associated with significantly higher biological age at a given chronological age and that this is a pathway to early death both overall and from the major age-related diseases.

Debilitating events could leave either more frail or more robust survivors, depending on the extent of scarring and mortality selection. The majority of empirical analyses find more frail survivors. I find heterogeneous effects. Among severely stressed former Union Army prisoners of war (POWs), the effect that dominates 35 years after the end of the Civil War depends on age at imprisonment. Among survivors to 1900, those younger than 30 at imprisonment faced higher old-age mortality and morbidity and worse socioeconomic outcomes than non-POW and other POW controls, whereas those older than 30 at imprisonment faced a lower older-age death risk than the controls.

This article uses data from the United States, Jamaica, Malaysia, and Bangladesh to explore gender differences in adult health. The results show that women fare worse than men across a variety of self-reported health measures in all four countries studies. These health status disparities between men and women persist even after appropriate corrections are made for the impact of (a) differential mortality selection by gender and (b) sociodemographic factors. Data from Jamaica indicate that gender disparities in adult health arise early and persist throughout the life cycle, with different age profiles for different measures.The US, Jamaica, Malaysia, and Bangladesh have different levels of socioeconomic development, life styles, gender norms, and expectations. The authors use survey data on measures of general health and physical functioning by age and gender in their study of differential gender patterns in adult health and their determinants. The study found that there are significant gender differences in adult health, with women faring worse than men across a variety of measures in all four countries studied. Health status disparities between the sexes persist even after correcting for the impact of differential mortality selection by gender and sociodemographic factors such as age, education, income, and location of respondent. Biological factors, behavioral factors, and reporting biases have all been suggested as explanations for these gender differences in adult ill health. Given the consistency of the gender disparity in adult ill health across different measures and countries with different levels of education, income, life styles, and norms and expectations about behavior as illustrated in this study, however, reporting bias is most likely not a major cause of gender differentials in adult health. The fact that significant gender differentials in adult health persist despite controlling for sociodemographic characteristics points instead to the need for further research into the behavioral and biological bases of the differentials.

Data from three rounds of nationally representative health surveys in India (1992/93, 1998/99 and 2005/06) are used to assess the impact of selective mortality on children's anthropometrics. The nutritional status of the child population was simulated under the counterfactual scenario that all children who died in the first three years of life were alive at the time of measurement. The simulations demonstrate that the difference in anthropometrics due to selective mortality would be large only if there were very large differences in anthropometrics between the children who died and those who survived. Differences of this size are not substantiated by the research on the degree of association between mortality and malnutrition. The study shows that although mortality risk is higher among malnourished children, selective mortality has only a minor impact on the measured nutritional status of children stratified by gender.

Frontier populations provide exceptional opportunities to test the hypothesis of a trade-off between fertility and longevity. In such populations, mechanisms favoring reproduction usually find fertile ground, and if these mechanisms reduce longevity, demographers should observe higher postreproductive mortality among highly fertile women. We test this hypothesis using complete female reproductive histories from three large demographic databases: the Registre de la population du Québec ancien (Université de Montréal), which covers the first centuries of settlement in Quebec; the BALSAC database (Université du Québec à Chicoutimi), including comprehensive records for the Saguenay-Lac-St-Jean (SLSJ) in Quebec in the nineteenth and twentieth centuries; and the Utah Population Database (University of Utah), including all individuals who experienced a vital event on the Mormon Trail and their descendants. Together, the three samples allow for comparisons over time and space, and represent one of the largest set of natural fertility cohorts used to simultaneously assess reproduction and longevity. Using survival analyses, we found a negative influence of parity and a positive influence of age at last child on postreproductive survival in the three populations, as well as a significant interaction between these two variables. The effect sizes of all these parameters were remarkably similar in the three samples. However, we found little evidence that early fertility affects postreproductive survival. The use of Heckman’s procedure assessing the impact of mortality selection during reproductive ages did not appreciably alter these results. We conclude our empirical investigation by discussing the advantages of comparative approaches. Am. J. Hum. Biol. 21:533–540, 2009.

A review of health data identified four major trends in the elderly population: (a) a younger Black group that was more morbid than an older Black group, (b) an alternating pattern of Black morbid and robust age groups, (c) a Black disadvantage in health and functioning that was greater in race comparisons involving the Black morbid and less in comparisons involving the Black robust age groups, and (d) a Black health detriment that seemed to narrow at age 85. The trends suggest that age and health are more strongly related in the White elderly than in the Black elderly population. The trends also are compatible with the more rapid growth of Blacks aged 85 and over than any other group of the elderly, adverse mortality selection processes, and the racial mortality crossover. Issues for new research that will explain these four trends are discussed.

This chapter evaluates age reporting among the oldest-old, especially centenarians, in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) based on comparisons of various indices of elderly age reporting and age distributions of centenarians in Sweden, Japan, England and Wales, Australia, Canada, China, the USA, and Chile. The analyses demonstrate that age reporting among the oldest-old interviewees (Han and six minority groups combined) in the 22 provinces in China where the CLHLS has been conducted is not as good as that in Sweden, Japan, and England and Wales, but is relatively close to that in Australia, more or less the same as that in Canada, better than that in the USA (all race groups combined), and much better than that in Chile. As indicated by the higher density of centenarians, age exaggeration exists in the six ethnic minority groups in the 22 Han-dominated provinces, although we cannot rule out and quantify the potential impacts of past mortality selection and better natural environmental conditions among these minority groups. We find that the age exaggeration of minorities in the CLHLS may not cause substantial biases in demographic and statistical analyses using the CLHLS data, since minorities consist of a rather small portion of the sample (6.8 percent at baseline and 5.5 percent in the grand total sample of the 1998, 2000, and 2002 waves).

We find that the Kannisto model, a two-parameter logistic formula, fits Han Chinese death rates at oldest-old ages better than the Gompertz and four other models. Chinese death rates appear to be roughly similar to Swedish and Japanese rates after age 97 for both males and females. Because reports of age seem to be serviceably reliable up to age 100 and perhaps age 105 in China, we think that this convergence may be mainly due to mortality selection in the heterogeneous Chinese population. We show that in China, as in developed countries, the rate of increase in mortality with age decelerates at very old ages.

The impact of SES on mortality is an established fact. I examine if this impact decreases with increasing age. Most research finds that it does so but it is unknown whether this decrease is due to mortality selection. The data I use come from the US-Health and Retirement Study, which surveyed 9376 persons aged 59 and over from 1992 to 2000. The variables allow for a time varying measurement of SES, health and behavior. Event-history-analysis is applied to analyze differences in mortality rates. My results show that socioeconomic mortality differences are stable across ages whereas they clearly decline with decreasing health. My first finding, that health rather than age is the equalizer combined with the second finding, that good health itself is unequally distributed, leads to the conclusion that in old age, the impact of SES is transferred to the health status and hence it is stable across ages.

Models of gender differences in human mortality and aging depend on assumptions about temporal rates of physiological change. Simple models like the Gompertz fail to describe the mortality of either males or females at late ages. This suggests a need for biologically more detailed models to represent the age dependency of human mortality as well as gender differences in that age dependence. By modeling the sex-specific interaction of time-varying covariates with multiple dimensions of mortality selection, one can more accurately describe the age dependence of mortality and more complex physiological aging patterns. The multivariate model of aging changes is used to describe gender differences using data from (a) a longitudinal study of physiological changes and mortality and (b) a nationally representative longitudinal survey of changes in function and mortality.

Methods are presented which produce Maximum Likelihood Estimates (MLE) of the degree of heterogeneity in individual mortality risks under a variety of assumptions about the age trajectory of those mortality risks. With these estimates of the degree of population heterogeneity it is possible to adjust comparisons of mortality risks across populations for the effects of population heterogeneity, differential mortality selection, and different age trajectories of the force of mortality. These methods are demonstrated by applying a variety of standard assumptions about the age trajectory of the force of mortality to the analysis of a broad range of cohort mortality data for the U.S. and Swedish populations. The estimates of the degree of heterogeneity, produced under all of the selected force of mortality models, consistently indicated a considerable degree of heterogeneity in mortality risks.

A number of theoretical models of aging and human mortality have been proposed. Only a few of these theoretical models, however, have been translated into statistical procedures and applied to data. In this paper we outline a theoretical model of human aging and mortality and compare it with models developed by Sacher and Trucco and Forbes and Brown. The ways in which this new model can be viewed as a generalization of these other formulations are discussed as are ways in which this model can be translated into a statistical model for empirical application.