Demographic Research

Online ISSN: 1435-9871
Publications
2006 Family listing visit outcomes for all MDICP respondents, and respondents interviewed in 2004 
Article
In this paper we evaluate the quality of survey data collected by the Malawi Diffusion and Ideational Change Project by investigating four potential sources of bias: sample representativeness, interviewer effects, response unreliability, and sample attrition. We discuss the results of our analysis and implications of our findings for the collection of data in similar contexts.
 
Article
PIP This paper presents the completed series of life tables from 1751 to 1995 that was used in identifying the four stages of mortality transition in Finland, separated by the years 1880, 1945, and 1970. The series documents all the different stages of mortality transition from high to low levels in an originally agricultural country experiencing many wars, famines, and other crises, as well as major political change. The cyclical fluctuation of the death rate in the 18th and 19th centuries is measured and examined in relation to epidemics, famines, and wars. Important permanent changes in mortality also took place in this period. Each of the successive stages of transition produced its own characteristic pattern of mortality change, which contrasted with those of the other stages. Finally, the age profile of the years added to life is drawn to illustrate the end result of each stage of mortality transition.
 
Article
This study explores the change of married women's sex preference for children in Taiwan since 1990, finding that there was a substantial decline of son preference and rise of "gender indifference", defined as feeling indifferent about children's sex (as opposed to desiring an equal number of boys and girls, in which the sex of children is still a primary consideration). Results show that at the individual level female education was the strongest predictor for the preference; education was negatively associated with son preference and positively with gender indifference. Cohort difference was noticeable, too. Younger cohorts were better educated than older ones so that they were more neutral about the sex and less adherent to the traditional male preference; besides, from 1992 to 2002 there was a universal intra-cohort movement toward gender neutrality and away from son preference. When the younger cohorts gradually replaced the older ones as the main child bearers in the Taiwanese society, at the aggregate level son preference declined and gender indifference rose.
 
Article
Same-sex couples are less likely to be homogamous than different-sex couples on a variety of characteristics including race/ethnicity, age, and education. This study confirms results from previous studies which used 1990 U.S. census data and extends previous analyses to examine changes from 1990 to 2000. We find that same-sex male cohabitors are generally the least likely to resemble one another, followed by same-sex female cohabitors, different-sex cohabitors, and different-sex married couples. Despite estimated growth in the numbers of same-sex couples in the population and the increasing acceptance of same-sex unions, we find little evidence of diminishing differences in the resemblance of same- and different-sex couples between 1990 and 2000, with the possible exception of educational homogamy.
 
Article
The paper examines changes in the relationship between employment and household tasks of Japanese couples, using data drawn from national cross-sectional surveys in 1994, 2000 and 2009 of persons aged 20-49 and from the 2009 follow-up of the 2000 survey. Wives' employment is structured by their husbands' employment time and earning power, as well as by their family situations including the presence and age of children and coresidence with parents. Housework hours of husbands, though very low, increased over time, while wives' hours decreased. Wives housework time decreases as their employment time increases. Marriage dramatically increases women's housework time but produces little change in men's time. Husbands' housework hours are positively correlated with reported marital satisfaction of both spouses.
 
Article
In the absence of HIV testing, how do rural Malawians assess their HIV status? In this paper, we use a unique dataset that includes respondents' HIV status as well as their subjective likelihood of HIV infection. These data show that many rural Malawians overestimate their likelihood of current HIV infection. The discrepancy between actual and perceived status raises an important question: Why are so many wrong? We begin by identifying determinants of self-assessed HIV status, and then compare these assessments with HIV biomarker results. Finally, we ask what characteristics of individuals are associated with errors in self-assessments.
 
Article
Brazil has witnessed dramatic changes in its fertility patterns in recent decades. The decline to below-replacement fertility has been accompanied by increases in the proportion of children born to young mothers. Yet we know little about the well-being of children born to young mothers in Brazil. Using data from the 2006 Pesquisa Nacional de Demografia e Saúde and a quasi-natural experimental approach, this study examines the implications of maternal age at first birth for the education of Brazilian adolescents. We find that being born to a young mother is associated with educational disadvantages in adolescence, but that these disadvantages are attenuated once we account for mothers' selection into early childbearing. We also find that, in southern Brazil, adolescents born to young mothers have poorer educational outcomes compared with their peers born to older mothers, but that in northern Brazil no such disparities exist. Adolescent educational disadvantages associated with being born to a young mother are not an artifact of selectivity, at least in southern Brazil. Regional variation in the effect of maternal age at first birth on adolescent education suggests the important role of the extended family and the father's presence as mechanisms through which disadvantages operate.
 
Article
Unobserved differences in individual's susceptibility to death are an important aspect in the analysis of contemporary mortality patterns. However, observed mortality rates at adult ages, which are usually well described by a Gompertz curve, are often perceived inconsistent with frailty models of mortality. The authors therefore propose a modified DeMoivre hazard function that is suitable for the application of frailty models to adult and old ages. The proposed hazard increases faster than exponential, and when combined with unobserved frailty it can capture a broad range of patterns encountered in the analysis of adult mortality. The authors' application to Bulgaria during 1992-93 suggests that the stronger selection process in the male population, caused by an overall higher level of mortality, may constitute a primary mechanism leading to the convergence of male and female mortality at higher ages. Hence, the convergence between male and female mortality is not necessarily caused by differential process of aging across sexes, but is merely a consequence of the different levels of mortality at adult ages.
 
Article
We investigate the sex-age-specific changes in the mortality of a prospectively monitored rural population in South Africa. We quantify changes in the age pattern of mortality in a parsimonious way by estimating the eight parameters of the Heligman-Pollard (HP) model of age-specific mortality. In its traditional form this model is difficult to fit and does not account for uncertainty. 1. To quantify changes in the sex-age pattern of mortality experienced by a population with endemic HIV. 2. To develop and demonstrate a robust Bayesian estimation method for the HP model that accounts for uncertainty. Bayesian estimation methods are adapted to work with the HP model. Temporal changes in parameter values are related to changes in HIV prevalence. Over the period when the HIV epidemic in South Africa was growing, mortality in the population described by our data increased profoundly with losses of life expectancy of ~15 years for both males and females. The temporal changes in the HP parameters reflect in a parsimonious way the changes in the age pattern of mortality. We develop a robust Bayesian method to estimate the eight parameters of the HP model and thoroughly demonstrate it. Changes in mortality in South Africa over the past fifteen years have been profound. The HP model can be fit well using Bayesian methods, and the results can be useful in developing a parsimonious description of changes in the age pattern of mortality. The motivating aim of this work is to develop new methods that can be useful in applying the HP eight-parameter model of age-specific mortality. We have done this and chosen an interesting application to demonstrate the new methods.
 
Article
Despite considerable concern regarding the social consequences of sub-Saharan Africa's high orphan prevalence, no research investigates how living in a community densely populated with orphans is more broadly associated with children's-including nonorphans'-acquisition of human capital. We provide a new look at the implications of widespread orphanhood in sub-Saharan Africa by examining whether living in an area with a high concentration of orphans is associated with children's likelihood of school enrollment. We use data from the Demographic and Health Survey (DHS) and the Multiple Indicators Cluster Survey (MICS) to estimate multilevel logistic regression models to assess whether living in a setting with a higher concentration of orphans is associated with school enrollment among 383,010 children in 336 provinces in 34 sub-Saharan African countries. Orphan concentration has a curvilinear association with children's school enrollment in western and eastern Africa: the initially positive association becomes negative at higher levels. In central and southern Africa, orphan concentration has a positive linear association with children's school enrollment. In western and eastern Africa, the negative association between living in a setting more densely populated with orphans and children's school enrollment provides suggestive evidence that the orphan disadvantage "spills over" in the communities most heavily affected. Conversely, in central and southern Africa, the positive association between living in a setting more densely populated with orphans and children's school enrollment highlights the resiliency of these relatively wealthier communities with high levels of orphans. Although longitudinal research is needed to confirm these findings and clarify the underlying mechanisms, this study lays the groundwork for a new body of research aimed at understanding the broader social implications of widespread orphanhood in sub-Saharan Africa.
 
Event history calendar scheme  
Map of birthplace by sex among study subjects, Ghana (upper panel) and Greater Accra (lower panel) Note: Red dots signify women and blue dots men. The lower panel includes a star indicating the location of Agbogbloshie in Accra.  
Article
BACKGROUND HIV is spread through structured sexual networks, which are influenced by migration patterns, but network-oriented studies of mobility and HIV risk behavior have been limited. OBJECTIVE We present a comprehensive description and initial results from our Migration & HIV in Ghana (MHG) study in Agbogbloshie, an urban slum area within Accra, Ghana. METHODS The MHG study was a population-based cross-sectional study of adults aged 18–49 in Agbogbloshie in 2012. We used a one-year retrospective relationship history calendar to collect egocentric network data on sexual partners as well as migration and short-term mobility, and tested for prevalent HIV-1/2 infection. RESULTS HIV prevalence was 5.5%, with prevalence among women (7.2%) over twice that of men (2.8%). Three-quarters of residents were born outside the Greater Accra region, but had lived in Agbogbloshie an average of 10.7 years. Only 7% had moved housing structures within the past year. However, short-term mobility was common. Residents had an average of 7.3 overnight trips in the last year, with women reporting more travel than men. Thirty-seven percent of men and 9% of women reported more than one sexual partner in the last year. CONCLUSIONS Population-based surveys of migration and sexual risk behavior using relationship history calendars in low-resource settings can produce high quality data. Residents in Agbogbloshie are disproportionately affected by HIV, and have high levels of short-term mobility. HIV prevention interventions targeted to highly mobile populations in high prevalence settings may have far-reaching and long-term implications.
 
Article
This article presents an extension of the cohort-component model of population projection (CCMPP) first formulated by Heuveline (2003) that is capable of modeling a population affected by HIV. Heuveline proposes a maximum likelihood approach to estimate the age profile of HIV incidence that produced the HIV epidemics in East Africa during the 1990s. We extend this work by developing the Leslie matrix representation of the CCMPP, which greatly facilitates the implementation of the model for parameter estimation and projection. The Leslie matrix also contains information about the stable tendencies of the corresponding population, such as the stable age distribution and time to stability. Another contribution of this work is that we update the sources of data used to estimate the parameters, and use these data to estimate a modified version of the CCMPP that includes (estimated) parameters governing the survival experience of the infected population. A further application of the model to a small population with high HIV prevalence in rural South Africa is presented as an additional demonstration. This work lays the foundation for development of more robust and flexible Bayesian estimation methods that will greatly enhance the utility of this and similar models.
 
Article
Intergenerational transfer patterns in sub-Saharan Africa are poorly understood, despite the alleged importance of support networks to ameliorate the complex implications of the HIV/AIDS epidemic for families. There is a considerable need for research on intergenerational support networks and transfers to better understand the mechanisms through which extended families cope with the HIV/AIDS epidemic and potentially alleviate some of its consequences in sub-Saharan Africa, and to comprehend how transfers respond-or not-to perceptions about own and other family members' health. Using the 2008 round of the Malawi Longitudinal Study of Families and Health (MLSFH), we estimate the age patterns and the multiple directions of financial and non-financial transfer flows in rural Malawi-from prime-aged respondents to their elderly parents and adult children age 15 and up. We also estimate the social, demographic and economic correlates of financial and non-financial transfers of financial intergenerational transfers in this context. Our findings are that: (1) intergenerational financial and non-financial transfers are widespread and a key characteristic of family relationships in rural Malawi; (2) downward and upward transfers are importantly constrained and determined by the availability of transfer partners (parents or adult children); (3) financial net transfers are strongly age-patterned and the middle generations are net-providers of transfers; (4) non-financial transfers are based on mutual assistance rather than reallocation of resources; and (5) intergenerational transfers are generally not related to health status, including HIV positive status.
 
Article
AIDS-related morbidity and mortality are expected to have a large economic impact in rural Malawi, because they reduce the time that adults can spend on production for subsistence and on income-generating activities. However, households may compensate for production losses by reallocating tasks among household members. The data demands for measuring these effects are high, limiting the amount of empirical evidence. In this paper, we utilize a unique combination of qualitative and quantitative data, including biomarkers for HIV, collected by the 2004 Malawi Diffusion and Ideational Change Project, to analyze the association between AIDS-related morbidity and mortality, and time allocation decisions in rural Malawian households. We find that AIDS-related morbidity and mortality have important economic effects on women's time, whereas men's time is unresponsive to the same shocks. Most notably, AIDS is shown to induce diversification of income sources, with women (but not men) reallocating their time, generally from work-intensive (typically farming and heavy chores) to cash-generating tasks (such as casual labor).
 
Weighted percentage distributions of demographic characteristics of married and cohabiting individuals in the 2009 French, 2008 Italian, and 2003-2007 American Time Use Surveys 
Article
Women, who generally do more unpaid and less paid work than men, have greater incentives to stay in marriages than cohabiting unions, which generally carry fewer legal protections for individuals that wish to dissolve their relationship. The extent to which cohabitation is institutionalized, however, is a matter of policy and varies substantially by country. The gender gap in paid and unpaid work between married and cohabiting individuals should be larger in countries where cohabitation is less institutionalized and where those in cohabiting relationships have relatively fewer legal protections should the relationship dissolve, yet few studies have explored this variation. Using time diary data from France, Italy, and the United States, we assess the time men and women devote to paid and unpaid work in cohabiting and married couples. These three countries provide a useful diversity in marital regimes for examining these expectations: France, where cohabitation is most "marriage like" and where partnerships can be registered and carry legal rights; the United States, where cohabitation is common but is short-lived and unstable and where legal protections vary across states; and Italy, where cohabitation is not common and where such unions are not legally acknowledged and less socially approved than in either France or the United States. Cohabitating men's and women's time allocated to market and nonmarket work is generally more similar than married men and women. Our expectations about country differences are only partially borne out by the findings. Greater gender differences in the time allocated to market and nonmarket work are found in Italy relative to either France or the U.S.
 
Article
Citizenship status among the foreign born is a crucial indicator of social and political incorporation, yet there are good reasons to suspect that citizenship status is inaccurately reported on U.S. surveys. This paper updates research carried out in the mid-1990s by Passel and Clark (1997) on the extent to which foreign-born non-citizen respondents in U.S. government-sponsored surveys misreport as naturalized citizens. We compare demographic estimates of the resident naturalized foreign-born population in 2010, based on administrative data, to estimates from the 2010 American Community Survey (ACS). Similar to previous research, we find that misreporting in the ACS is especially high among immigrants from all countries/regions who report fewer than five years in the U.S. We also find that among longer-term foreign-born residents, misreporting is concentrated only among those originating in Mexico, especially men, a finding that diverges from Passel and Clark in that we find no evidence of over-reporting among immigrants from Central America and the Caribbean. Finally, the estimated magnitude of misreporting, especially among longer-term Mexican-born men, is sensitive to assumptions about the rate of emigration in our administrative-based demographic estimates, and assumptions about coverage error in the ACS, though altering these assumptions does not change the conclusions drawn from the general patterns of the results. For applications that use citizenship as an indicator of legal status, we recommend that self-reported data on citizenship be accepted at face value for all groups except those with less than five years of U.S. residence and Mexican men.
 
Article
Against a backdrop of two new developments in the fertility behavior of the Mexican-Origin population in the U.S., the present discussion will update contemporary Mexican-Origin fertility patterns and address several theoretical weaknesses in the current approach to immigrant group fertility. Data come from six national surveys (three from Mexico and three from the U.S.) that cover a twenty-five year period (1975- 2000). The findings demonstrate dramatic decreases in the fertility rates in Mexico at the same time that continuous increases have been documented in the fertility rates of native-born Mexican-Americans in the U.S. at younger ages. These changes necessitate a reexamination of the idea that Mexican pronatalist values are responsible for the high fertility rates found within the Mexican-Origin population in the U.S. Instead, they point to the increasing relevance of framing the fertility behavior of the Mexican-Origin population within a racial stratification perspective that stresses the influence of U.S. social context on fertility behavior. As a step in this direction, the analysis examines fertility patterns within the Mexican-Origin population in the U.S., giving special attention to the role of nativity/generational status in contributing to within group differences.
 
Article
While there is a rich literature on the practice of child fostering in sub-Saharan Africa, little is known about how fostering impacts receiving households, as few studies consider household conditions both before and after fostering. Despite the fact that circumstances surrounding fostering vary, the literature's key distinction of fostering is often drawn along the simple line of whether or not a household is fostering a child. This paper argues that anticipation of fostering responsibilities, in particular, is a useful dimension to distinguish fostering experiences for receiving households. This paper examines the relationship between receiving a foster child and subsequent changes in household wealth. Particular emphasis is placed on how these changes are conditioned by differing levels of anticipation of the fostering event. This study uses data from Tsogolo la Thanzi (TLT), a longitudinal survey in Balaka, Malawi. Using data from 1754 TLT respondents, fixed effects pooled time-series models are estimated to assess whether and how receiving a foster child changes household wealth. This paper demonstrates the heterogeneity of fostering experiences for receiving households. The results show that households that anticipate fostering responsibilities experience a greater increase in household wealth than both households that do not foster and those that are surprised by fostering. Households that anticipate fostering responsibilities exhibit the greatest increase in household wealth. While fostering households that do not anticipate fostering responsibilities may not experience these gains, there is no evidence to indicate that such households are negatively impacted relative to households that do not foster. This finding suggests that additional childcare responsibilities may not be as detrimental to African households as some researchers have feared.
 
Article
We use two surveys to describe the demographic and attitudinal correlates of being in "Living Apart Together" (LAT), cohabiting, and marital relationships for heterosexuals, lesbians, and gay men. About one third of U.S. adults not married or cohabiting are in LAT relationships - these individuals would be classified as "single" in conventional studies that focus on co-residential unions. Gay men are somewhat more likely than heterosexual men to be in LAT relationships. For heterosexuals and lesbians, LAT relationships are more common among younger people. Heterosexuals in LAT unions are less likely to expect to marry their partners, but more likely to say that couples should be emotionally dependent than are cohabiters. Regardless of sexual orientation, people in LAT relationships perceive similar amounts of emotional support from partners, but less instrumental support than cohabiters perceive.
 
Article
Testing for HIV is becoming more available in Africa. Global advocates of testing see it as key to AIDS prevention. However, testing is not always perceived as a good thing by people at risk. Here, we consider testing from the perspective of people in a high-prevalence community. Using qualitative data from rural Malawi, we show that the decision to test is not as straightforward as suggested in the testing advocacy literature, but is marked by uncertainty and ambivalence. Reluctance to test is connected to the perception that testing inevitably leads to a positive diagnosis, and subsequent deterioration and death. This fear is in turn linked to overestimation of the transmissibility of HIV. We recommend that testing advocates address this concern that being tested means having a death sentence pronounced, and emphasize the benefits of testing for the majority who are HIV-negative, as well as the minority who are HIV-positive.
 
Histogram of LMUP raw scores. Samata Health Study, Bangalore, India (n=971)  
(Continued)  
Differences in LMUP scores between first and second administrations, one year apart  
Item Characteristic Curves a for LMUP items  
Article
We evaluated the psychometric properties of the London Measure of Unplanned Pregnancy among Indian women using classical methods and Item Response Modeling. The scale exhibited good internal consistency and internal structure, with overall scores correlating well with each item's response categories. Items performed similarly for pregnant and non-pregnant women, and scores decreased with increasing parity, providing evidence for validity. Analyses also detected limitations, including infrequent selection of middle response categories and some evidence of differential item functioning by parity. We conclude that the LMUP represents an improvement over existing measures but recommend steps for enhancing scale performance for this cultural context.
 
Article
Based on the unique longitudinal data of the elderly aged 65+ with a sufficiently large sub-sample of the oldest-old aged 85+ from the Chinese Longitudinal Healthy Longevity Survey, we construct a resilience scale with 7 indicators for the Chinese elderly, based on the framework of the Connor-Davidson Resilience Scale. Cox proportional hazards regression model estimates show that, after controlling for socio-demographic characteristics and initial health status, the total resilience score and most factors of the resilience scale are significantly associated with reduced mortality risk among the young-old and oldest-old. Although the causal mechanisms remain to be investigated, effective measures to promote resilience are likely to have a positive effect on longevity of the elderly in China.
 
Mean number of children ever born to men ages 35-44 in seven European countries by attitude toward gender equality in two studies 
Article
An analysis published in a recent edition of this journal (Puur, Olah, Tazi-Preve, and Dorbritz 2008) reported that, in eight European countries, men with egalitarian gender attitudes both desired and had more children than men with more traditional gender attitudes. These unexpected findings led us to explore a similar research question with an alternate dataset--the European/World Value Surveys. But we found--without exception--a negative association between men's egalitarian attitudes and fertility, not only in the selected eight European countries but also in a considerable number of other developed countries. We explore possible reasons for and implications of these divergent findings.
 
Article
PIP This study investigates the relationship between month of birth and life span. It uses 2 different data for total populations in Austria and Denmark. The Austrian data are based on vital statistics of the exact data of birth and the exact date of death for each person dying after age 50 between 1988 and 1996. The Danish data consist of the total population aged 50+ on April 1, 1968. These people were then followed until their death or until August 1998. Results suggest that life span and month of birth were in fact related. Evidences were presented to support or argue the three hypotheses being tested that explain the relationship between month of birth and longevity. Overall, many studies support that this pattern was not the result of the seasonal distribution of death. And the longevity cannot be explained by the so-called ¿birthday-effect¿--the alleged tendency of people to die shortly after their birthday. Instead, the study concluded by discussing the possible social and biological mechanisms related to a person's season of birth that might influence life expectancy.
 
Article
This multicenter study has produced a database of 7017 menstrual cycles contributed by 881 women. It provides improved knowledge on length and location of the "fertile window" (identified as of up to 12 days duration) and the patterns and level of daily conception probability. The day of ovulation was identified in each cycle from records of basal body temperature and mucus symptoms. By referencing days of intercourse to the surrogate ovulation markers, estimates of daily fecundability were computed either directly or by the Scwartz model, both for single and multiple acts of intercourse in the fertile window. The relationship between coital pattern and fecundability has been explored. Univariate analysis underlines the significant link with fecundability only of the woman's reproductive history.
 
Article
Much of our knowledge of the epidemiology and demography of HIV epidemics in Africa is derived from models fit to sparse, non-representative data. These often average over age and other important dimensions, rarely quantify uncertainty, and typically do not impose consistency on the epidemiology and the demography of the population. This work conducts an empirical investigation of the history of the HIV epidemic in Uganda and Tanzania through the late 1990s, focusing on sex-age-specific incidence, uses those results to produce probabilistic forecasts of HIV prevalence ten years later, and compares those to measures of HIV prevalence at the later time to describe the sex-age pattern of changes in prevalence over the intervening period. We adapt an epidemographic model of a population affected by HIV so that its parameters can be estimated using both the Bayesian melding with IMIS estimation method and maximum likelihood methods. Using the Bayesian version of the model we produce probabilistic forecasts of the population with HIV. We produce estimates of sex-age-specific HIV incidence in Uganda and Tanzania in the late 1990s, produce probabilistic forecasts of the HIV epidemics in Uganda and Tanzania during the early 2000s, describe the sex-age pattern of changes in HIV prevalence in Uganda during the early 2000s, and compare the performance and results of the Bayesian and maximum likelihood estimation procedures. We demonstrate that: (1) it is possible to model HIV epidemics in Africa taking account of sex and age, (2) there are important advantages to the Bayesian estimation method, including rigorous quantification of uncertainty and the ability to make probabilistic forecasts, and (3) that there were important age-specific changes in HIV incidence in Uganda during the early 2000s.
 
Article
Although previous studies have indicated that performance assessments strongly predict future survival, few have evaluated the incremental value in the presence of controls for self-reported activity and mobility limitations. We assess and compare the added value of four tests - walking speed, chair stands, grip strength, and peak expiratory flow (PEF) - for predicting all-cause mortality. Using population-based samples of older adults in Costa Rica (n = 2290, aged 60+) and Taiwan (n = 1219, aged 53+), we estimate proportional hazards models of mortality for an approximate five-year period. Receiver Operator Characteristic (ROC) curves are used to assess the prognostic value of each performance assessment. Self-reported measures of physical limitations contribute substantial gains in mortality prediction, whereas performance-based assessments yield modest incremental gains. PEF provides the greatest added value, followed by grip strength. Our results suggest that including more than two performance assessments may provide little improvement in mortality prediction. PEF and grip strength are often simpler to administer in home interview settings, impose less of a burden on some respondents, and, in the presence of self-reported limitations, appear to be better predictors of mortality than do walking speed or chair stands. Being unable to perform the test is often a strong predictor of mortality, but these indicators are not well-defined. Exclusion rates vary by the specific task and are likely to depend on the underlying demographic, health, social and cultural characteristics of the sample.
 
Article
Despite the centrality of religion and fertility to life in rural Africa, the relationship between the two remains poorly understood. The study presented here uses unique integrated individual and congregational level data from rural Malawi to examine religious influences on contraceptive use. In this religiously diverse population, we find evidence that the particular characteristics of a congregation-leader's positive attitudes toward family planning and discussion of sexual morality, which do not fall along broad denominational lines-are more relevant than denominational categories for predicting women's contraceptive use. We further find evidence for a relationship between religious socialization and contraceptive behavior.
 
Article
Biodemography has emerged and grown over the last fifteen years, with loyal and farsighted support from its patrons. As it enters what might be called its adolescence as a field, it faces challenges along with abounding opportunities. One challenge is to continue to generate knowledge that contributes to human health and well-being. A second is to insist on high standards of quality control within its crossdisciplinary environment. Opportunities appear in a variety of directions, including mathematical modeling, genomic analyses, and field studies of aging in the wild.
 
Sex ratio at birth (SRB) in China, 1970-2005.  
Total fertility rate (TFR) in China, 1949-1991.  
Article
Fertility decline, driven by the one-child policy, and son preference have contributed to an alarming difference in the number of live male and female births in China. We present a quantitative model where people choose to sex-select because they perceive that married sons are more valuable than married daughters. Due to the predominant patrilocal kinship system in China, daughters-in-law provide valuable emotional and financial support, enhancing the perceived present value of married sons. We argue that inter-generational transfer data will help ascertain the extent to which economic schemes (such as pension plans for families with no sons) can curtail the increasing sex ratio at birth.
 
Article
BACKGROUND: Limited information is available about teenage pregnancy and childbearing in rural areas, even though approximately 20 percent of the nation's youth live in rural areas. Identifying whether there are differences in the teenage birth rate (TBR) across metropolitan and nonmetropolitan areas is important, because these differences may reflect modifiable ecological-level influences such as education, employment, laws, healthcare infrastructure, and policies that could potentially reduce the TBR. OBJECTIVES: The goals of this study are to investigate whether there are spatially varying relationships between the TBR and the independent variables, and if so, whether these associations differ between metropolitan and nonmetropolitan counties. METHODS: We explore the heterogeneity within metropolitan/nonmetropolitan county groups separately using geographically weighted regression (GWR), and investigate the difference between metropolitan/nonmetropolitan counties using spatial regime models with spatial errors. These analyses were applied to county-level data from the National Center for Health Statistics and the US Census Bureau. RESULTS: GWR results suggested that non-stationarity exists in the associations between TBR and determinants within metropolitan/nonmetropolitan groups. The spatial regime analysis indicated that the effect of socioeconomic disadvantage on TBR significantly varied by the metropolitan status of counties. CONCLUSIONS: While the spatially varying relationships between the TBR and independent variables were found within each metropolitan status of counties, only the magnitude of the impact of the socioeconomic disadvantage index is significantly stronger among metropolitan counties than nonmetropolitan counties. Our findings suggested that place-specific policies for the disadvantaged groups in a county could be implemented to reduce TBR in the US.
 
Non-parametric estimates of transitions to second birth (ECHP 1994-2000)  
Fertility, unemployment, and fixed-term contracts in Spain, 1972-2006
Article
This paper analyzes how labor market instability since the late 1980s in Europe mediated decisions to second births. In particular, it examines which are the dimensions of economic uncertainty that affect women with different educational backgrounds. First, employing time varying measures of aggregate market conditions for women in twelve European countries as well as micro-measures of each woman's labor market history, it shows that delays in second births are significant in countries with high unemployment, among women who are unemployed, particularly the least educated, and who have temporary jobs. Holding a very short contract is more critical than unemployment for college graduates. Second, using the 2006 Spanish Fertility Survey, it presents remarkably similar findings for Spain, the country with the most dramatic changes in both fertility and unemployment in the last decades: a high jobless rate and the widespread use of limited-duration contracts were correlated with a substantial postponement of second births.
 
Age-specific death rates for U.S. women: 2000 Source: Human Mortality Database (2008). 
Article
The rate of mortality increase with age among adults is typically used as a measure of the rate of functional decline associated with aging or senescence. While black and white populations differ in the level of mortality, mortality also rises less rapidly with age for blacks than for whites, leading to the well-known black/white mortality "crossover". This paper investigates black/white differences in the rate of mortality increase with age for major causes of death in order to examine the factors responsible for the black/white crossover. The analysis considers two explanations for the crossover: selective survival and age misreporting. Mortality is modeled using a Gompertz model for 11 causes of death from ages 50-84 among blacks and whites by sex. Mortality increases more rapidly with age for whites than for blacks for nearly all causes of death considered. The all-cause mortality rate of mortality increase is nearly two percentage points higher for whites. The analysis finds evidence for both selective survival and age misreporting, although age misreporting is a more prominent explanation among women. The black/white mortality crossover reflects large differences in the rate of age-related mortality increase. Instead of reflecting the impact of specific causes of death, this pattern exists across many disparate disease conditions, indicating the need for a broad explanation.
 
Article
Using life table measures, we compare educational differentials in all-cause mortality at ages 40 to 70 in Bulgaria to those in Finland and the United States. Specifically, we assess whether the relationship between education and mortality is modified by marital status. Although high education and being married are associated with lower mortality in all three countries, absolute educational differences tend to be smaller among married than unmarried individuals. Absolute differentials by education are largest for Bulgarian men, but in relative terms educational differences are smaller among Bulgarian men than in Finland and the U.S. Among women, Americans experience the largest education-mortality gradients in both relative and absolute terms. Our results indicate a particular need to tackle health hazards among poorly educated men in countries in transition.
 
Article
It has been established that under certain mortality assumptions, the current value of the Cross-sectional Average length of Life (CAL) is equal to the life expectancy for the cohort currently reaching its life expectancy. This correspondence is important, because the life expectancy for the cohort currently reaching its life expectancy, or lagged cohort life expectancy (LCLE), has been discussed in the tempo literature as a summary mortality measure of substantive interest. In this paper, we build on previous work by evaluating the extent to which the correspondence holds in actual populations. We also discuss the implications of the CAL-LCLE correspondence (or lack thereof) for using CAL as a measure of cohort life expectancy, and for understanding the connection between CAL, LCLE, and underlying period mortality conditions.
 
Article
Recent studies indicate that the traditional rural-urban dichotomy pointing to cities as places of better health in the developing world can be complicated by poverty differentials. Knowledge of spatial patterns is essential to understanding the processes that link individual demographic outcomes to characteristics of a place. A significant limitation, however, is the lack of spatial data and methods that offer flexibility in data inputs. This paper tackles some of the issues in calculating intra-urban child mortality by combining multiple data sets in Accra, Ghana and applying a new method developed by Rajaratnam et al. (2010) that efficiently uses summary birth histories for creating local-level measures of under-five child mortality (5q0). Intra-urban 5q0 rates are then compared with characteristics of the environment that may be linked to child mortality. Rates of child mortality are calculated for 16 urban zones within Accra for birth cohorts from 1987 to 2006. Estimates are compared to calculated 5q0 rates from full birth histories. 5q0 estimates are then related to zone measures of slum characteristics, housing quality, health facilities, and vegetation using a simple trendline R(2) analysis. Results suggest the potential value of the Rajaratnam et al. method at the micro-spatial scale. Estimated rates indicate that there is variability in child mortality between zones, with a spread of up to 50 deaths per 1,000 births. Furthermore, there is evidence that child mortality is connected to environmental factors such as housing quality, slum-like conditions, and neighborhood levels of vegetation.
 
Article
This paper examines the living arrangements of Swedish children from 1970 through 1999 using the Level of Living Survey. Sweden, with low levels of economic inequality and a generous welfare state, provides an important context for studying socioeconomic differentials in family structure. We find that, although differences by parent education in non-marital childbearing are substantial and persistent, cohabiting childbearing is common even among highly educated Swedish parents. Educational differences in family instability were small during the 1970s, but increased over time as a result of rising union disruption among less-educated parents (secondary graduates or less). Children in more advantaged families experienced substantially less change in family structure and instability over the study period. Although cohabiting parents were more likely to separate than parents married at the child's birth, differences were greater for the less-educated. Data limitations precluded investigating these differences across time. We conclude that educational differences in children's living arrangements in Sweden have grown, but remain small in international comparisons.
 
Ghana's Central Region. (Study area includes the six coastal districts, outlined in green.)  
Predicted probability of inter-regional move (by sex, residence and education) from Model 2, Table 3  
Article
This article uses life history calendar (LHC) data from coastal Ghana and event history statistical methods to examine inter-regional migration for men and women, focusing on four specific migration types: rural-urban, rural-rural, urban-urban, and urban-rural. Our analysis is unique because it examines how key determinants of migration- including education, employment, marital status, and childbearing-differ by sex for these four types of migration. We find that women are significantly less mobile than men overall, but that more educated women are more likely to move (particularly to urban areas) than their male counterparts. Moreover, employment in the prior year is less of a deterrent to migration among women. While childbearing has a negative effect on migration, this impact is surprisingly stronger for men than for women, perhaps because women's search for assistance in childcare promotes migration. Meanwhile, being married or in union appears to have little effect on migration probabilities for either men or women. These results demonstrate the benefits of a LHC approach and suggest that migration research should further examine men's and women's mobility as it relates to both human capital and household and family dynamics, particularly in developing settings.
 
Article
Scholars have recently become increasingly interested in the role religion plays in the responses to the HIV/AIDS epidemic in sub-Saharan Africa. Here, we present the Malawi Religion Project (MRP), which provides data to examine the relationship between religion and HIV/AIDS through surveys and in-depth interviews with denominational leaders, congregational leaders, and congregation members in three districts of rural Malawi. In the paper, we outline existing perspectives on the religion-HIV/AIDS link, describe the MRP's design, implementation, and subsequent data; provide initial evidence for a series of general research hypotheses; and describe how these data can be used both to extend explorations of these relationships further and as a model for gathering similar data in other contexts. In particular we highlight the unique possibilities this project provides for analyses that link MRP data to the Malawi Diffusion and Ideational Change Project. These linked data produce a multi-level data set covering individuals, congregations and their communities, allowing empirical research on religion, HIV/AIDS risk, related behaviors, attitudes, and norms.
 
Article
Although longitudinal experimental community health research is crucial to testing hypotheses about the demographic impact of health technologies, longitudinal demographic research field stations are rare, owing to the complexity and high cost of developing requisite computer software systems. This paper describes the Household Registration System (HRS), a software package that has been used for the rapid development of eleven surveillance systems in sub-Saharan Africa and Asia. Features of the HRS automate software generation for a family surveillance applications, obviating the need for new and complex computer software systems for each new longitudinal demographic study.
 
Article
To address the question of whether sex differences in mortality will in the future rise, fall, or stay the same, this study uses relative smoking prevalence among males and females to forecast future changes in relative smoking-attributed mortality. Data on 21 high income nations from 1975 to 2000 and a lag between smoking prevalence and mortality allow forecasts up to 2020. Averaged across nations, the results for logged male/female ratios in smoking mortality reveal equalization of the sex differential. However, continued divergence in non-smoking mortality rates would counter convergence in smoking mortality rates and lead to future increases in the female advantage overall, particularly in nations at late stages of the cigarette epidemic (such as the United States and the United Kingdom).
 
(2030 DALYs per Capita)/(2005 DALYs per Capita): Overall and Three Major GBD/WHO Aggregates with HIV/AIDS Also Separate 
Article
In this paper, we present a framework for considering whether the marginal social benefits of demographic and social science research on various health conditions in developing countries are likely to be relatively high. Based on this framework, we argue that the relative current and future predicted prevalence of burdens of different health/disease conditions, as measured by disability-adjusted life years (DALYs), provide a fairly accurate reflection of some important factors related to the relative marginal social benefits of demographic and social science research on different health conditions. World Health Organization (WHO) DALYs projections for 2005-30 are compared with (a) demographic and other social science studies on health in developing countries during 1990-2005, and (b) presentations made at the Population Association of America annual meetings during the same time period. These comparisons suggest that recent demographic and social science research on health in developing countries has focused too much on HIV/AIDS, and too little on non-communicable diseases.
 
Article
Extensive research in both developed and developing countries has shown that preferences and intentions for future childbearing predict behavior. However, very little of this research has examined high-fertility contexts in sub-Saharan Africa. In particular, the factors that increase or decrease correspondence between fertility desires and behavior in these settings are not well understood. This article documents the degree to which the desire to stop childbearing predicts fertility behavior over the short term among married women in rural southern Mozambique, a context where fertility transition is still in the early stages. Analyses test the moderating powers of individual, household, and community characteristics. Analyses use data from a longitudinal survey of married women of reproductive age (N=1678) carried out in 2006 and 2009 in rural areas of southern Mozambique. Logistic regression models are estimated to predict childbearing between 2006 and 2009 based on desires to stop childbearing and characteristics measured in 2006. As expected, the desire to stop childbearing is strongly predictive of fertility behavior. Household wealth, local adult AIDS mortality, and being married to an unsuccessful labor migrant are associated with higher correspondence between reported desire to stop childbearing and fertility behavior. Both factors related to the ability to carry out desires to stop childbearing and factors related to the strength and consistency of these desires moderate the association between desires and behaviors. Future research should expand measurement of fertility preferences to incorporate their strength and consistency as well as direction.
 
Article
Estimating the total fertility rate is challenging for many developing countries because of limited data and varying data quality. A standardized, reproducible approach to produce estimates that include an uncertainty assessment is desired. We develop a method to estimate and assess uncertainty in the total fertility rate over time, based on multiple imperfect observations from different data sources, including surveys and censuses. We take account of measurement error in observations by decomposing it into bias and variance, and assess both by linear regression on a variety of data quality covariates. We estimate the total fertility rate using a local smoother, and assess uncertainty using the weighted likelihood bootstrap. We apply our method to data from seven countries in West Africa and construct estimates and uncertainty intervals for the total fertility rate. Based on cross-validation exercises, we find that accounting for differences in data quality between observations gives better calibrated confidence intervals and reduces bias. When working with multiple imperfect observations from different data sources to estimate the total fertility rate, or demographic indicators in general, potential biases and differences in error variance should be taken into account to improve the estimates and their uncertainty assessment.
 
C: Convergence of SEs for HE estimates for non-Hispanic white women at age 65  
A: Convergence of SEs for HE estimates for non-Hispanuc white men at age 65  
Distribution of years spent in active health for 65-year old men  
Distribution of years spent in disability for 65-year old men  
Article
The multistate life table (MSLT) model is an important demographic method to document life cycle processes. In this paper, we present the SPACE (Stochastic Population Analysis for Complex Events) program to estimate MSLT functions and their sampling variability. It has several advantages over other programs, including the use of micro-simulation and the bootstrap method to estimate the variance of MSLT functions. Simulation enables researchers to analyze a broader array of statistics than the deterministic approach, and may be especially advantageous in investigating distributions of MSLT functions. The bootstrap method takes sample design into account to correct the potential bias in variance estimates.
 
Article
At this time there are 37 demographic surveillance system sites active in sub-Saharan Africa, Asia and Central America, and this number is growing continuously. These sites and other longitudinal population and health research projects generate large quantities of complex temporal data in order to describe, explain and investigate the event histories of individuals and the populations they constitute. This article presents possible solutions to some of the key data management challenges associated with those data. The fundamental components of a temporal system are identified and both they and their relationships to each other are given simple, standardized definitions. Further, a metadata framework is proposed to endow this abstract generalization with specific meaning and to bind the definitions of the data to the data themselves. The result is a temporal data model that is generalized, conceptually tractable, and inherently contains a full description of the primary data it organizes. Individual databases utilizing this temporal data model can be customized to suit the needs of their operators without modifying the underlying design of the database or sacrificing the potential to transparently share compatible subsets of their data with other similar databases. A practical working relational database design based on this general temporal data model is presented and demonstrated. This work has arisen out of experience with demographic surveillance in the developing world, and although the challenges and their solutions are more general, the discussion is organized around applications in demographic surveillance. An appendix contains detailed examples and working prototype databases that implement the examples discussed in the text.
 
Article
Despite extensive research, doubts remain regarding the degree of correspondence between prior stated fertility preferences and subsequent fertility behavior. Preference instability is a factor that potentially undermines predictiveness. Furthermore, if other predictors of fertility substantially explain fertility, then knowledge of preferences may contribute little to explaining or predicting individual fertility behavior. In this study, we examined these aspects of the study of individual fertility preference-behavior consistency. Using a prospective multi-wave panel dataset, we modeled the monthly likelihood of conception, taking into account the dynamic nature of preferences, and controlling for changing reproductive life cycle factors and stable socioeconomic background predictors of fertility. We demonstrate from a sample of fecund married Ghanaian women that fertility preferences retain independent predictive power in the model predicting the likelihood of conception.
 
Article
In this paper we explore patterns of economic transfers between adults within household and family networks in a village in Malawi's Rumphi district, using data from the 2006 round of the Malawi Longitudinal Study of Families and Health. We fit Exponential-family Random Graph Models (ERGMs) to assess individual, relational, and higher-order network effects. The network effects of cyclic giving, reciprocity, and in-degree and out-degree distribution suggest a network with a tendency away from the formation of hierarchies or "hubs." Effects of age, sex, working status, education, health status, and kinship relation are also considered.
 
Article
Demographic and health surveillance (DS) systems monitor and document individual and group-level processes in well-defined populations over long periods of time. The resulting data are complex and inherently temporal. Established methods of storing and manipulating temporal data are unable to adequately address the challenges posed by these data. Building on existing standards, a temporal framework and notation are presented that are able to faithfully record all of the time-related information (or partial lack thereof) produced by surveillance systems. The Unified Timestamp isolates all of the inherent complexity of temporal data into a single data type and provides the foundation on which a Unified Timestamp class can be built. The Unified Timestamp accommodates both point- and interval-based time measures with arbitrary precision, including temporal sets. Arbitrary granularities and calendars are supported, and the Unified Timestamp is hierarchically organized, allowing it to represent an unlimited array of temporal entities.
 
Article
Extra-marital sexual partnerships (EMSPs) are a major route of HIV/AIDS transmission in sub-Saharan Africa. In this paper, we investigate the roles of two types of male friendships - best friends and friends with whom they talk about AIDS - in determining whether men have EMSPs. Using data from men in rural Malawi, we find that men's current extra-marital sexual behavior is most closely correlated with their best friends', but that the behaviors of both types of friends are associated with men's subsequent EMSPs. These findings suggest that men's friendships could be used to help combat the AIDS epidemic.
 
Top-cited authors
Tomas Sobotka
  • Austrian Academy of Sciences (OeAW)
Jan M. Hoem
  • Max Planck Institute for Demographic Research
Hans-Peter Kohler
  • University of Pennsylvania
Andres Vikat
  • United Nations Economic Commission for Europe
Michaela Kreyenfeld
  • Hertie School of Governance