Infant mortality in the Marshall Islands

Levy and Booth present previously unpublished infant mortality rates for the Marshall Islands. They use an indirect method to estimate infant mortality from the 1973 and 1980 censuses, then apply indirect and direct methods of estimation to data from the Marshall Islands Women's Health Survey of 1985. Comparing the results with estimates of infant mortality obtained from vital registration data enables them to estimate the extent of underregistration of infant deaths. The authors conclude that 1973 census appears to be the most valid information source. Direct estimates from the Women's Health Survey data suggest that infant mortality has increased since 1970-1974, whereas the indirect estimates indicate a decreasing trend in infant mortality rates, converging with the direct estimates in more recent years. In view of increased efforts to improve maternal and child health in the mid-1970s, the decreasing trend is plausible. It is impossible to estimate accurately infant mortality in the Marshall Islands during 1980-1984 from the available data. Estimates based on registration data for 1975-1979 are at least 40% too low. The authors speculate that the estimate of 33 deaths per 1000 live births obtained from registration data for 1984 is 40-50% too low. In round figures, a value of 60 deaths per 1000 may be taken as the final estimate for 1980-1984.     

Measuring maternal mortality through the census: rapier or bludgeon?

There is increased demand for maternal mortality estimates as a result of the choice of the Maternal Mortality Ratio as the key indicator for Millennium Development Goal 5. Given this strong demand, the United Nations Principles and Recommendations for Population Censuses suggest the inclusion of questions on recent household deaths, plus questions to identify pregnancy-related deaths in countries lacking empirical, national estimates. This paper evaluates the results of census-based measurement of pregnancy-related mortality using three different types of consistency checks applied in selected countries. Results from these evaluations are mixed. Overall, the census approach seems to produce robust estimates of the number of births. However, the consistency and plausibility of results relating to mortality vary substantially by country and by indicator. It is not clear whether the census-based methodology performs better or worse than the frequently used sibling histories. The results presented here clearly demonstrate the need for careful data evaluation and interpretation.     

Bayesian population reconstruction of female populations for less developed and more developed countries

We show that Bayesian population reconstruction, a recent method for estimating past populations by age, works for data of widely varying quality. Bayesian reconstruction simultaneously estimates age-specific population counts, fertility rates, mortality rates, and net international migration flows from fragmentary data, while formally accounting for measurement error. As inputs, Bayesian reconstruction uses initial bias-reduced estimates of standard demographic variables. We reconstruct the female populations of three countries: Laos, a country with little vital registration data where population estimation depends largely on surveys; Sri Lanka, a country with some vital registration data; and New Zealand, a country with a highly developed statistical system and good quality vital registration data. In addition, we extend the method to countries without censuses at regular intervals. We also use it to assess the consistency of results between model life tables and available census data, and hence to compare different model life table systems.     

Estimation of vital rates for Ghana

Abstract A complete and efficient registration system, of the type which would provide good data on births and deaths, does not exist in Ghana. However, registration of vital events is supposed to be compulsory in 39 towns in the country but the data collected in these areas are too inadequate and defective to provide a sound basis for the analysis of the dynamics of population growth. The results of the censuses conducted by the colonial governments are so defective and unreliable that they do not allow scientific research in the field of population analysis. Before 1960, therefore, when the national census and the post-enumeration survey (based on a 5% sample of the population) were carried out, estimates of fertility and mortality levels were little more than guesses. In this study an attempt has been made to utilize the information on the age-sex composition provided by the 1960 census and post-enumeration survey data on births and deaths to determine, as far as possible, the levels of fertility and mortality and the rates of population growth in Ghana. The fertility estimates-i.e. a crude birth rate of 50, total fertility rate of 6.9 and a gross reproduction rate of 3.4-show that Ghana's fertility is one of the highest in the world. An expectation of life at birth of 40 years, an infant mortality of 160 and a crude death rate of 23 appear to be the most plausible estimates. These estimates yield a rate of natural increase of 2.7% and a growth rate of 3.0% per annum.     

Lifetime risk of pregnancy-related death among Zambian women: district-level estimates from the 2010 census

The aim of this study was to examine district differentials in the lifetime risk of pregnancy-related death among females aged 15–49 in Zambia. We used data on household deaths collected in the 2010 census to estimate the lifetime risk of pregnancy-related death among females in Zambia. Using all-cause age-specific death rates, we generated female life tables for 74 districts and estimated person-years of exposure to all-cause mortality at each age. We then applied age-specific pregnancy-related mortality rates to the person-years of exposure to obtain estimates of adult lifetime risk that took account of competing causes of death. We used the ArcGIS software to analyse clustering and the spatial distribution of risk. A female aged 15 in Zambia had a 3.7 % chance of dying a pregnancy-related death before the age of 50. At district level, the lifetime risk ranged from 1.7 to 7.7 %. The Global Moran’s I was 0.452 (z-score 5.8, p value <0.01), indicating clustering of districts with similar risk levels of pregnancy-related mortality. Clustering of high-risk districts was found in Western province while clustering of low risk districts was found in Lusaka and Muchinga provinces. The level of adult lifetime risk was more positively associated with pregnancy-related mortality than with fertility. Females in Zambia have a high lifetime risk of pregnancy-related death overall but this risk varies greatly across the different districts of the country. The observed diversity is larger than when merely studying differences between provinces and is only weakly linked to differences in fertility levels. The identification of districts with varying levels of risk should enable evidence-based and focused delivery of maternal health services in districts where risk of death from maternal causes is greatest.     

Bayesian Estimation of Age-Specific Mortality and Life Expectancy for Small Areas With Defective Vital Records

High sampling variability complicates estimation of demographic rates in small areas. In addition, many countries have imperfect vital registration systems, with coverage quality that varies significantly between regions. We develop a Bayesian regression model for small-area mortality schedules that simultaneously addresses the problems of small local samples and underreporting of deaths. We combine a relational model for mortality schedules with probabilistic prior information on death registration coverage derived from demographic estimation techniques, such as Death Distribution Methods, and from field audits by public health experts. We test the model on small-area data from Brazil. Incorporating external estimates of vital registration coverage though priors improves small-area mortality estimates by accounting for underregistration and automatically producing measures of uncertainty. Bayesian estimates show that when mortality levels in small areas are compared, noise often dominates signal. Differences in local point estimates of life expectancy are often small relative to uncertainty, even for relatively large areas in a populous country like Brazil.     

Revising Infant Mortality Rates for the Early Twentieth Century United States

Accurate vital statistics are required to understand the evolution of racial disparities in infant health and the causes of rapid secular decline in infant mortality during the early twentieth century. Unfortunately, U.S. infant mortality rates prior to 1950 suffer from an upward bias stemming from a severe underregistration of births. At one extreme, African American births in southern states went unregistered at the rate of 15 % to 25 %. In this study, we construct improved estimates of births and infant mortality in the United States for 1915–1940 using recently released complete count decennial census microdata combined with the counts of infant deaths from published sources. We check the veracity of our estimates with a major birth registration study completed in conjunction with the 1940 decennial census and find that the largest adjustments occur in states with less-complete birth registration systems. An additional advantage of our census-based estimation method is the extension backward of the birth and infant mortality series for years prior to published estimates of registered births, enabling previously impossible comparisons and estimations. Finally, we show that underregistration can bias effect estimates even in a panel setting with specifications that include location fixed effects and place-specific linear time trends.     

Maternal mortality in South Africa: an update from the 2007 Community Survey

The 2007 Community Survey conducted in South Africa included questions on maternal deaths in the previous 12 months (pregnancy-related deaths). The Maternal Mortality Ratio (MMR) was estimated at 702 per 100,000 live births, some 30% more than at the 2001 census. This high level occurred despite a low proportion of maternal deaths (4.3%) among deaths of women aged 15–49 years, which is even lower than the proportion of time spent in the maternal risk period (7.6%). The high level of MMR was due to the astonishingly high level of adult mortality, which increased by 46% since 2001. The main reasons for these excessive levels were HIV/AIDS and external causes of death (accidents and violence). Differentials in MMR were very marked, and similar to those found in 2001 with respect to urban residence, race, province, education, income, and wealth. Provincial levels of MMR correlated primarily with HIV/AIDS prevalence. Maternal mortality defined as ‘pregnancy-related death’ appears no longer as a proper indicator of ‘safe motherhood’ in this situation.     

A method for deriving mortality estimates from incomplete vital Statistics

Summary Although they are available in many developing countries vital registration records are very little used for mortality estimation which is still mainly based on census returns. However, defective death records may yield accurate estimations of mortality. This procedure requires few data only; a sex-age distribution of the population (preferably at the middle of a period) and a sexage distribution of deaths, either derived from vital records or from census returns to questions relating to deaths during the preceding twelve months. This method is based on the observation that for a fixed age structure of the population, there is a one-one relation between the age structure of deaths (measured by the proportion of deaths at older ages) and the level of mortality (measured by the death rate above a certain minimum age). It is assumed that at ages above this minimum the rate of underregistration of deaths does not vary significantly with age. Therefore, the age distribution of registered deaths makes it possible to estimate the true proportion of deaths at older ages. This in its turn will permit the estimation of the true level of mortality, because of the relation which exists between age structure of deaths and level of mortality. The true level is then compared with the observed, to estimate the rate of underregistration, and observed age-specific death rates can be adjusted in the light of this knowledge.     

Estimating infant mortality trends from child survivorship data

Summary Brass's procedure for estimating mortality from census or survey data on numbers of children born to women by age group and numbers of children surviving is generalized to allow the estimation of mortality trends. The new procedure is applied to data for Costa Rica and peninsular Malaysia. The resulting infant mortality rate estimates are compared with rates calculated from vital registration figures. The comparisons suggest, surprisingly, that the estimates derived from statistics for women aged 30-50 are not noticeably inferior to those derived from those for women aged 20-30. This suggests that the common practice of disregarding statistics for women aged over 30 or 35 years may be a mistake. Figures are presented which suggest that estimates based on women aged less than 20 are likely to be very seriously biased because of differential infant mortality by age of mother at birth.     

Vital rates in India 1961-71 estimated from 1971 census data

Abstract In the last decade the increase in the population of India, while, of course, very large, was smaller than predicted by official forecasts. With the use of recent census and sample registration data - in the absence of age-specific rates and adequate vital statistics - this paper provides estimates of fertility and mortality through the reverse-survival and forward-projection methods. Birth rates are estimated as 40·5-42, death rates as 18-20, and life expectancy at birth as 45-46 years. Mortality decline had been smaller than forecast but more than during any comparable period in the past, even though current mortality levels, particularly infant mortality, are still high. Males continue to have a longer life expectation than females, with a difference that has widened in the past decade. The decline of between seven and ten per cent in the crude birth rate is largely due to changes in marital fertility and to some extent to changes in age and marital composition. Because of greater decline in death rates than birth rates, the 1961-71 decade shows a higher rate of population growth than previous periods.     

Estimating the completeness of death registration

Summary Death registration statistics, even when incomplete, can provide valuable information about mortality. In particular, the age structure of deaths can be used to estimate the completeness of registration, provided that this completeness does not vary substantially with age. Two methods of estimating the completeness of death registration from the distribution of deaths by age are described. The first is derived from stable population theory and requires an estimate of the rate of natural increase of the population, as well as assuming stability. However, the technique can also be used to generate simultaneously estimates of the rate of natural increase and of death registration completeness. The second method which requires two census age distributions and intercensal deaths by age, estimates the relative enumeration completeness of the two censuses as well as the completeness of death registration and requires only that the population be closed. Results are sensitive to overstatement of age. The methods are illustrated by being applied to figures from Thailand for the period 1960-70 and are found to work satisfactorily.     

Estimating Mortality Level for Small Populations: An Evaluation of a Pair of Two-Census Methods

A pair of two-census methods of estimating mortality levels are tested with simulated census data. The populations considered range in size from 250 to 1500 individuals of each sex; censuses were taken at intervals of five and ten years. In general, the methods are resistant to bias, and yield variances similar in magnitude to those obtained using vital registration data and life table techniques for censored data. The two-census methods represent a substantial improvement over the techniques of mortality estimation previously available for small populations, since two reliable censuses are more likely to be available for these populations than complete vital registration.     

Estimating census and death registration completeness

This article presents a new method for estimating the relative completeness of 2 census enumerations and of intercensal registered deaths. The Growth Balance Equation was developed by Brass (1975) to estimate the completeness of death registration relative to the completeness of census enumeration. The method presented here can be seen either as an extension of Martin's formulation to allow explicitly for changes in census coverage or as a modification of Brass's method to use deaths by age group rather than deaths by cohort, preferable on the grounds that age group comparisons will be less distorted by age misreporting than cohort comparisons if the patterns of age misreporting are similar for 2 successive censuses. This simple method estimates simultaneously the relative coverage of the 2 censuses and the completeness of registration of intercensal deaths. The key assumptions of the method are that the population is closed to migration and that all the coverage factors involved are invariant with age, at least for the age range studied. Analysis of the sensitivity of the estimates to the assumptions and further work on extending the method to open populations would be useful.     

Gender Inequality,Maternal Mortality and Inclusive Growth in Nigeria

The relevance of women in contributing to inclusive growth and consequently economic development in Nigeria cannot be overemphasized. Women play important social, economic and productive roles in any economy. Maternal mortality rate refers to the annual number of deaths of women from pregnancy-related causes per 100,000 live births, and Nigeria’s rate is still relatively high at about 630 when compared with the figures of the developed countries. For inclusive growth to be achieved in Nigeria, women should not be neglected and marginalized so they can contribute their quota to the growth of the country, but maternal mortality rate needs to be reduced because it is only the living that can make contributions to growth. Thus, this study examined the long run effect of gender inequality, maternal mortality and inclusive growth in Nigeria using time series data spanning from 1985 to 2017, and employed the ARDL econometric technique. The results showed that gender inequality and maternal mortality have negative impacts on inclusive growth in Nigeria. Therefore, the study recommends that women should be properly taken care of during pregnancy so that the maternal mortality rate can be reduced and hence they will be able to make meaningful contributions to the growth of the Nigerian economy.

     

Estimates of vital rates for the Canadian Indians, 1960–1970

The present paper is an attempt to evaluate the registered data on Canadian Indians collected by the Department of Indian Affairs and Northern Development and to prepare vital rates for 1960–1970 using the adjusted data. A cursory examination of registered data for the purpose of developing various demographic indices and for making future estimates of population indicates certain anomalies that call for a careful appraisal of the data. The main problem is the inconsistency in the reporting of births, due largely to the late registration of births. One plausible reason for late registration may be the increased outward movement of Indians from their reserves. Indirect methods are used to adjust the number of births and infant deaths reported annually since 1960. On the basis of the adjusted data, vital rates for the Canadian Indians are calculated for the period 1960–1970. The crude death rate decreased from 10.9 in 1960 to 7.5 in 1970. The infant mortality rate registered a drastic decline, from 81.5 deaths per 1,000 births in 1960 to 34.9 in 1970. During this same time period the birth rate also declined, from 46.5 to 37.2.     

Annual fertility rates from census data on own children: Comparisons with vital statistics data for the United States

This paper begins by describing the procedure and data requirements for calculating annual fertility rates from census data on own children. Then, using data from the United States Censuses of 1960 and 1970, fully adjusted estimates are presented and compared with recorded vital statistics rates. Total fertility estimates derived from own children data for whites average less than two percent lower than the recorded rates- a difference that can be attributed partially to the fact that the estimates are adjusted for net census undercount but the recorded rates are not. Even without adjustments for mortality, children not living with their mothers, and net census undercount, the own children data estimates accurately replicate recorded trends (even though the levels are misspecified). The utility of own children data for the study of differential fertility is discussed.     

New african American life tables from 1935–1940 to 1985–1990*

New life tables for African Americans are presented from 1935 through 1990. They are based on a historical series of vital statistics data on deaths that have been corrected for age misreporting, on reconstructed population counts that have been adjusted for census underenumeration, and on births that have been corrected for underregistration. The new life tables show rapid mortality declines for both African American males and females from 1935 to 1950, and relatively steady reductions thereafter for females. The smaller declines in male mortality in young adulthood and middle age since the 1950s have led to exceptionally high ratios of male to female mortality at these ages. Corrections for census undercounts lead to higher values of life expectancy than in official life tables, but to less improvement over time. Official estimates of life expectancy at age 65 appear to be about 10% too high around 1940 but only about 1.5% too high in the late 1980s.     

Adult Mortality From Sibling Survival Data: A Reappraisal of Selection Biases

Because of incomplete registration of deaths in most countries in sub-Saharan Africa, data on the survival of close relatives constitute the cornerstone of estimates of adult mortality. Since 1990, sibling histories have been widely collected in Demographic and Health Surveys and are increasingly being relied upon to estimate both general and maternal mortality. Until recently, the use of sibling histories was thought to lead to underestimates of mortality, but a more optimistic view in the literature emerged with the development by Gakidou and King (Demography 43:569–585, 2006) of corrections for selection biases. Based on microsimulations, this article shows that Gakidou and King’s weighting scheme has been incorrectly applied to survey data, leading to overestimates of mortality, especially for males. The evidence for an association between mortality and sibship size in adulthood is reviewed. Female mortality appears to decline slightly with the number of surviving sisters, although this could be an artifact of severe recall errors in larger sibships or familial clustering of deaths. Under most circumstances, corrections for selection biases should have only a modest effect on sibling estimates.