Age reporting among white Americans aged 85+: Results of a record linkage study

This study investigates age reporting on the death certificates of older white Americans. We link a sample of death certificates for native-born whites aged 85+ in 1985 to Social Security Administration records and to records of the U.S. censuses of 1900, 1910, and 1920. When ages in these sources are compared, inconsistencies are found to be minimal, even beyond age 95. Results show little distortion and no systematic biases in the reported age distribution of deaths. To explore the effect of age misreporting on old-age mortality, we estimate "corrected" age-specific death rates by the extinct-generation method for the U.S. white cohort born in 1885. With few exceptions, corrected and uncorrected rates in single years differ by less than 3% and are not systematically biased. When we compare corrected rates with those for the same birth cohort in France, Japan, and Sweden, we find that white American mortality at older ages is exceptionally low.     

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.     

Comparison of information on death certificates and matching 1960 census records: age,marital status,race, nativity and country of origin

A sample of death certificates matched with 1960 Census records permitted comparison of response data for items asked on both records. Estimates of bias in death rates which are based on information from the two records are derived from the comparison data. Most of the comparisons yielded small discrepancies of inconsequential effect on the mortality rates. Some large inconsistencies, however, of potentially serious impact on the death rates were observed. The comparisons are examined and the implications of the results for the relevant mortality rates are discussed. In addition, age-specific death rates "corrected" for the disparities found in the age information on the two records are presented.     

A description of the extreme aged population based on improved medicare enrollment data

The mortality and size of the extreme aged population can be studied most accurately with Medicare enrollment data from the Social Security Administration's Master Beneficiary Record after certain types of questionable records are eliminated. With the improved data base we find that mortality rates at the very old ages are higher than published rates, we are more confident of the reality of the race crossover, and we can estimate the number of centenarians more accurately. Furthermore, a large matched-records study shows close agreement on age at death between the Master Beneficiary Record and the death certificate.     

Accuracy of death certificate ages for the extreme aged

This study attempts to verify age reporting on the death certificate for the “extreme aged” population and to evaluate the accuracy of recent death rates for this group in light of the findings. In addition, methods used and problems encountered in carrying out a record linkage study, particularly a low match rate, are identified. A sample of more than three thousand death records was selected from those filed for decedents age 85 and over in Pennsylvania and New Jersey in the 1968 to 1972 period. Death certificates of 53 percent of whites and 30 percent of nonwhites were linked to the 1900 U.S. Census. A comparison of age on the death certificate with the age reported for the same individual in the census record showed a high level of agreement for whites, except at ages 100 and over; for nonwhites, however, age agreement levels were substantially lower. Within racial groups, there was little difference by sex in agreement on age. These results, corroborating those of earlier studies, make it clear that nonwhite mortality at the oldest ages has been consistently understated in official statistics.     

Estimating the completeness of reporting of adult deaths in populations that are approximately stable

An elaboration of Preston's (Preston and Hill, 1980) procedure for determining the completeness with which deaths are recorded in approximately stable populations is presented. Both the procedures of Preston and that of Brass are conventionally limited to mortality beyond early childhood, to mortality above age 5 or age 10. The method considered here is based on characteristics of stable populations, i.e., populations that have been subject for a long time to little variation in age-specific mortality schedules or in overall levels of fertility. The essential features of a stable population are maintained even if fertility has changed. This is the case as long as no strong trend in fertility existed more than 15 or 20 years before the date at which the population is observed. Recent changes in fertility may affect the structure of the population at adult ages, but the effect on estimates of completeness of death records can generally be kept within tolerably narrow limits. Prior to showing how explicit estimates of the relative completeness of recording of numbers of deaths and persons can be derived from counts of deaths and persons by age, it is noted that a life table for a stable population can be constructed directly from the recorded distribution of deaths by age, or from the recorded distribution of persons. The procedures described are applied to several different populations in order to illustrate the computational steps necessary to estimate the completeness of death records at ages above childhood in populations that are approximately stable.     

Russian Mortality Crisis and the Quality of Vital Statistics

Mortality from ill-defined conditions in Russia has the fastest rate of increase compared to all other major causes of death. High proportion of deaths in this category is indicative for low quality of mortality statistics. This article examines the trends and possible causes of mortality from ill-defined conditions in Russia. During 1991–2005, mortality from ill-defined conditions in Russia increased in all age groups. The pace of increase was particularly high at working ages and the mean expected age at death from ill-defined conditions has shifted to younger ages, particularly for men. The analysis of individual medical death certificates issued in Kirov and Smolensk regions of Russia demonstrate that 89–100% of working-age deaths from ill-defined conditions correspond to human bodies found in a state of decomposition. Data from Smolensk region shows that over 60% of these decedents were unemployed. Temporal trends of mortality from ill-defined conditions and injuries of undetermined intent in Moscow city suggest that deaths from the latter cause were probably misclassified as ill-defined conditions. This practice can lead to underestimation of mortality from external causes. Growing number of socially isolated marginalized people in Russia and insufficient investigation of the circumstances of their death contribute to the observed trends in mortality from ill-defined conditions.     

Separating the Signal From the Noise: Evidence for Deceleration in Old-Age Death Rates

Widespread population aging has made it critical to understand death rates at old ages. However, studying mortality at old ages is challenging because the data are sparse: numbers of survivors and deaths get smaller and smaller with age. I show how to address this challenge by using principled model selection techniques to empirically evaluate theoretical mortality models. I test nine models of old-age death rates by fitting them to 360 high-quality data sets on cohort mortality after age 80. Models that allow for the possibility of decelerating death rates tend to fit better than models that assume exponentially increasing death rates. No single model is capable of universally explaining observed old-age mortality patterns, but the log-quadratic model most consistently predicts well. Patterns of model fit differ by country and sex. I discuss possible mechanisms, including sample size, period effects, and regional or cultural factors that may be important keys to understanding patterns of old-age mortality. I introduce mortfit, a freely available R package that enables researchers to extend the analysis to other models, age ranges, and data sources.     

The Effect of Age Misreporting in China on the Calculation of Mortality Rates at Very High Ages

When mortality rates by age are calculated from recorded deaths and enumerated populations, rates at higher ages are typically in error because of misstated ages. Mortality rates for China in 1981 have been calculated from the number of deaths in 1981 in each household recorded in the 1982 census, and from the census population back-projected one year. Because age was determined from date of birth, and because persons of the Chinese culture have very precise knowledge of date of birth, the mortality rates even at high ages should be unusually accurate. This expectation is fulfilled for most of China, but severe misreporting of age is found in a province that contains a large minority of a non-Han nationality, which lacks precise knowledge of date of birth. Although the province contains only 1.3% of China's population, male death rates above age 90 for all of China are distorted seriously by the erroneous data from this location.     

Mortality in England and Wales from 1848 to 1947

This is a survey of the changing causes of death in England and Wales during the past 100 years. Based on the published mortality statistics of the General Register Office the framework of the survey is a series of specially prepared tables of death rates by sex, age and cause of death for the periods 1848–72, 1901–10, 1921, 1931, 1939 and 1947. Adjustments were made wherever necessary to compensate for changes in medical nomenclature and in the statistical classification of disease.

After allowance has been made for the changing age structure of the population, the male death rate at all ages in 1947 was 42% of the rate in 1846–50, and the female rate 35 %. Maximum improvement was among girls aged 5–9 years, whose death rate in 1947 was 9% of the rate 100 years before.

In 1848–72 the group to which were allocated the largest proportion of the deaths at all ages were the infectious diseases with one-third of the total; and these were followed by the respiratory, nervous and digestive diseases. In 1947, on the other hand, diseases of the circulatory system came first with rather more than one-third of the total at all ages, and these were followed by cancer.

Changes in proportionate mortality rates from various causes have been examined at successive ages from infancy to old age. There was a decline in proportionate mortality from the infectious diseases other than tuberculosis, but increased mortality from tuberculosis in the younger age groups and from violence, circulatory diseases and cancer.

The trends of absolute mortality from the various causes were also studied. The reduction in total mortality was such that whereas there were half a million deaths of civilians registered in England and Wales in 1947, the total would have been over a million had the death rates of 1848–72 still prevailed.

The article concludes with a brief review of the factors responsible for the changes that have taken place.     

Estimating African-American mortality from inaccurate data

This paper evaluates the quality of vital statistics and census data for estimating African-American mortality over a period of six decades. The authors employ intercensal cohort comparisons and extinct generation estimates to demonstrate that conventionally constructed African-American death rates may be seriously flawed as early as age 50. Using the crude death rate at ages 50+ for 1978-1982 in conjunction with estimated growth rates and two model life table systems, the authors estimate black age-specific death rates in 1978–1982. These results suggest that if a racial crossover in death rates occurs, the age pattern of mortality among African-Americans must be far outside the range observed in populations with more accurate data.     

Reproductive mortality in Georgia: A lifestyle and environmental analysis

Frequencies and rates of maternal mortality in the United States have declined sharply since the turn of the century. During this decline, researchers have closely examined maternal mortality relative to various risk factors. However, maternal death as currently defined and coded on death certificates may not reveal the true extent of the problem of reproductive mortality. In Georgia, an analysis of death certificates of females ages 10 to 49 indicates that deaths due to pregnancy related conditions are not being discovered by traditional underlying cause-of-death maternal mortality classification. Frequencies and rates were calculated showing the difference between the traditional International Classification of Disease codes for maternal deaths (ICD 630–676) and the reproductive mortality definition used in this paper (which emphasizes the Health Field Concept classification of Lifestyle, Environment, Biology and Health Care Delivery System) (Lalonde, M., 1974 and Laframboise, H. L., 1973). The analysis suggests that a revised definition of maternal mortality be employed to take into consideration all risk factors related to reproductive mortality.     

Racial differences in infant mortality by cause of death: The impact of birth weight and maternal age

This research examines racial disparities in infant mortality, overall and separately according to cause of death. Using linked birth and death records for the 1975 cohort of live births in Florida, racial differences are initially described and then explained statistically as a product of the distribution of births by birth weight and maternal age. The impact of birth weight is more pronounced than is the effect of maternal age. The analysis suggests the potential utility of examining infant mortality separately by cause of death. Based on the findings, we argue for systematic research focused on factors affecting birth weight.     

The cocos-keeling islands: A demographic laboratory

The Cocos Islands, which are situated in the Indian Ocean approximately halfway between Colombo and Fremantle, were first peopled early in the nineteenth century and were gradually developed as a very isolated coconut plantation with a labour force consisting partly of persons of Malay stock descended from the original group of settlers and partly of Bantamese contract labourers from Java. As the Cocos-born population increased in size, the dependence on contract labour decreased and, before the end of the century, all immigration ceased. The 1947 Malay population of the islands was about 1,800.

The islands are fascinating from a demographer's point of view because there was a virtually complete registration of live births, deaths and marriages and a partial registration of stillbirths. With these registration records it was possible to construct the life history of every individual from birth, through infancy and childhood to marriage, and thence through fatherhood or motherhood to death.

The picture revealed by an analysis of these records is that of a population with very high fertility and with mortality at a high level before the first World war and at a medium level after that war. Crude birth rates varied between 50 and 60 per thousand population during the period 1888 to 1947. Crude death rates were between 30 and 40 per thousand population until 1912 but under 2.0 per thousand population after 1918.

Most Cocos girls married before reaching the age of 20 and there were an average of between eight and nine live births per woman living through the childbearing period. There was a steady decline in the average number of live births with advancing age at marriage from age 16 onwards. A significantly high proportion of those dying in the middle of the childbearing period had never married, but the fertility of those marrying at an early age (14, 15 and 16) and dying before reaching the age of 36 was slightly higher than that of those who married at a similar age and survived. Women who survived to the age of 55 were of higher fertility than those who died between the ages of 40 and 55. An analysis of birth intervals revealed significant differences (a) between birth intervals after a stillbirth or after a live birth in which the child died in early infancy, and birth intervals after a live birth in which the offspring survived for longer than 0.4 years, and (b) between the interval from first to second birth and the subsequent birth intervals. There was a difference of almost exactly a year between the average birth interval after a stillbirth or live birth ending in a neo-natal death and the average birth interval after the birth of a child surviving to age 2; there was a similar difference of a year between corresponding median birth intervals.

From 1888 to 1912 infant mortality was well above 300 per thousand. After 1918 infant mortality averaged rather under 100 infant deaths per 1,000 live births. The reduction in infant mortality rates was accompanied by an increase in the mortality of children aged 1 to 4, and the heavy incidence of mortality at these ages after 1918 is the most striking feature of the analysis of mortality by age. Whilst mortality in infancy fell much more heavily on males than on females, early childhood mortality was much higher in Cocos for girls than for boys. The life table computed for the period 1918 to 1947 indicated a life expectancy of about 50 years for males and 47 years for females.     

Trends in Numbers and Mortality at High Ages in England and Wales

In the paper new estimates of the numbers of deaths and death rates at ages 80 and over in England and Wales are derived for the period 1911–90. These estimates were made by applying the methods of extinct generations and reverse survival to data on deaths in 1911–90, and pensioners in 1990. Estimates are given for individual years of age. It is found that death rates at these high ages have been falling, slowly, for the last 50 years. The paper also gives information on the highest ages at death which have been recorded and verified.     

Trends in senescent life expectancy

The distinction between senescent and non-senescent mortality proves to be very valuable for describing and analysing age patterns of death rates. Unfortunately, standard methods for estimating these mortality components are lacking. The first part of this paper discusses alternative methods for estimating background and senescent mortality among adults and proposes a simple approach based on death rates by causes of death. The second part examines trends in senescent life expectancy (i.e., the life expectancy implied by senescent mortality) and compares them with trends in conventional longevity indicators between 1960 and 2000 in a group of 17 developed countries with low mortality. Senescent life expectancy for females rises at an average rate of 1.54 years per decade between 1960 and 2000 in these countries. The shape of the distribution of senescent deaths by age remains relatively invariant while the entire distribution shifts over time to higher ages as longevity rises.     

Differences in mortality by marital status in Finland from 1976 to 2000: analyses of changes in marital-status distributions, socio-demographic and household composition, and cause of death

Being currently not married is more common today than 25 years ago. Over this period relative differences in mortality by marital status have increased in several countries, mainly as a result of a sharp decline in mortality among the married. Using Finnish census data linked with death certificates, we show that these increases are not explained by the non-married population becoming more marginalized in socio-economic status or household composition. However, the increases in marital-status differences in mortality from accidental, violent, and alcohol-related causes of death in the 30-64 age group indicate that changes in the health-related behaviour of the non-married population may play a role. The public-health burden associated with not being married has also grown. At the end of the 1990s about 15 per cent of all deaths above the age of 30 would not have occurred if the non-married population had had the same age-specific mortality rates as the married population.     

Demographic crisis: The impact of the Bangladesh civil war (1971) on births and deaths in a rural area of Bangladesh

Summary In Matlab Bazaar Thana the Cholera Research Laboratory has registered the births, deaths and migrations in a population of approximately 125,000 since 1966. Although this rural area was not the scene of any significant armed encounters, striking changes in birth and death rates were registered during and after the conflict. Birth rates did not change during the relatively brief period of the civil war, but a small decline was registered for one year after the war. Fertility rates which had been declining slightly and irregularly in the pre-war baseline period may have increased slightly during the war and fell substantially in all age groups in the year following the war. The crude death rate, which rose by 37 per cent during the war, was a very sensitive reflection of the administrative and economic problems. Overall infant mortality rose by only 15 per cent over pre-war levels because all of the increase was observed in the post-neo-natal component, which traditionally accounts for less than one-third of the total infant mortality in Bangladesh. Children and older adults accounted for the majority of excess deaths which were largely attributed to acute diarrhoeas and other gastro-intestinal causes. The death rate at ages 1-4 rose by 43 per cent and at ages 5-9 soared to 208 per cent above pre-war baseline rates. All increases in age-specific mortality rates fell to baseline levels during the year following the war, except the 5-9-year age group, in which rates continued to be high largely because of deaths due to dysentery.     

Revised regional model life tables at very low levels of mortality

This paper presents and discusses new model life tables at very low mortality, which make use of age-specific death rates from the 1960s, 1970s, and 1980s. These life tables fit recorded death rates in very low mortality populations better than do the existing ones at expectations of life of 77.5 and 80 years. The old tables incorporate too-high mortality at the higher ages and in infancy and they incorporate regional differences that no longer exist. The new tables "close out" the mortality schedules above age 80 more realistically. The convergence of age patterns of mortality at very high life expectancies in populations that used to conform to different families is in itself of demographic interest. Some convergence may perhaps be expected. Sullivan (1973) found that, in Taiwan, the comparison of mortality at ages 1-5 to mortality at 5-35 in the late 1950s showed higher mortality at the younger ages relative to the ensuing 30-year age interval than was found in any of the models, including the South model, which has the highest relative mortality from ages 1-5 among the 4 regional patterns. Then, in the late 1960s, the relation of mortality at 1-5 to mortality at 5-35 in Taiwan fell to a position intermediate between the West and South tables. Sullivan found in data on mortality by cause of death a large reduction in mortality from diarrhea and enteritis, no doubt as a result of environmental sanitation. Mortality from these causes is concentrated among young children, and reduction in deaths from these causes would naturally diminish the excess mortality in this age interval. The East pattern, characterized by very high mortality in infancy (but not from 1-5), may be the result of the prevalence of early weaning or avoidance of breast feeding altogether in the populations characterized by this pattern. As health conditions have improved, evidenced by the overall design of mortality, these special factors are diminished or erased. Model life tables at these very low mortality levels have different uses from most applications of model life tables at higher mortality. The use of model tables to estimate accurate schedules of mortality when the basic data are incomplete or inaccurate is less relevant in this range of mortality levels.     

Educational Inequality in Adult Mortality: An Assessment with Death Certificate Data from Michigan

Education was added to the U.S. Standard Certificate of Death in 1989. The current study uses Michigan’s 1989–1991 death certificates, together with the 1990 Census, to evaluate the quality of data on education from death certificates and to examine educational differences in mortality rates. With log-rates modeling, we systematically analyze the variability in educational differences in mortality by race and sex across the adult life cycle. The relative differences in mortality rates between educational levels decline with age at the same pace for all sex and race categories. Women gain a slightly greater reduction in mortality than men by reaching the secondary-education level, but a modestly smaller reduction by advancing beyond it. Blacks show a reduction in predicted mortality rates comparable to whites’ by moving from the secondary to the postsecondary level of education but experience less reduction than whites by moving from the primary to the secondary level. Thus, the secular decline in mortality rates that generally accompanies historical improvements in education might actually be associated with an increase in the relative differences between blacks’ and whites’ mortality. We discuss limitations of the data and directions for future research.