首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.

Background

Counties are the smallest unit for which mortality data are routinely available, allowing consistent and comparable long-term analysis of trends in health disparities. Average life expectancy has steadily increased in the United States but there is limited information on long-term mortality trends in the US counties This study aimed to investigate trends in county mortality and cross-county mortality disparities, including the contributions of specific diseases to county level mortality trends.

Methods and Findings

We used mortality statistics (from the National Center for Health Statistics [NCHS]) and population (from the US Census) to estimate sex-specific life expectancy for US counties for every year between 1961 and 1999. Data for analyses in subsequent years were not provided to us by the NCHS. We calculated different metrics of cross-county mortality disparity, and also grouped counties on the basis of whether their mortality changed favorably or unfavorably relative to the national average. We estimated the probability of death from specific diseases for counties with above- or below-average mortality performance. We simulated the effect of cross-county migration on each county''s life expectancy using a time-based simulation model. Between 1961 and 1999, the standard deviation (SD) of life expectancy across US counties was at its lowest in 1983, at 1.9 and 1.4 y for men and women, respectively. Cross-county life expectancy SD increased to 2.3 and 1.7 y in 1999. Between 1961 and 1983 no counties had a statistically significant increase in mortality; the major cause of mortality decline for both sexes was reduction in cardiovascular mortality. From 1983 to 1999, life expectancy declined significantly in 11 counties for men (by 1.3 y) and in 180 counties for women (by 1.3 y); another 48 (men) and 783 (women) counties had nonsignificant life expectancy decline. Life expectancy decline in both sexes was caused by increased mortality from lung cancer, chronic obstructive pulmonary disease (COPD), diabetes, and a range of other noncommunicable diseases, which were no longer compensated for by the decline in cardiovascular mortality. Higher HIV/AIDS and homicide deaths also contributed substantially to life expectancy decline for men, but not for women. Alternative specifications of the effects of migration showed that the rise in cross-county life expectancy SD was unlikely to be caused by migration.

Conclusions

There was a steady increase in mortality inequality across the US counties between 1983 and 1999, resulting from stagnation or increase in mortality among the worst-off segment of the population. Female mortality increased in a large number of counties, primarily because of chronic diseases related to smoking, overweight and obesity, and high blood pressure.  相似文献   

2.
Research about the economic consequences of past epidemics has mostly focused on the experience of industrialized countries, thus providing little knowledge about the effects of health shocks on developing economies. We fill this gap by studying the impact of the 1918 influenza in Java, with a new dataset on aggregate food production and district-level figures on (i) sugar production, the major export commodity and the predominant source of labour demand; (ii) agricultural and plantation wages, and (iii) annual crude death rates. The mortality impact of the influenza on Java was high, as crude mortality rates doubled in 1918 relative to the preceding years, but its economic impact was mixed. Aggregate food production did not decline, but sugar output did fall in 1919. Indeed, our regional panel data analysis does not establish a direct relationship between regional epidemic mortality variation and sugar output decline. Instead, we hypothesize that economic activity was rediverted towards food production in order to avoid famine that could have resulted from the combined effects of disrupted shipping at the end of the First World War, climatic conditions and the public health crisis. This is supported by both qualitative observations and quantitative evidence suggesting that those regions that were highly suitable for rice production saw a larger reduction in sugar production, and that in regions that had more flexibility in land tenure arrangements experienced substantially greater reductions in sugar output.  相似文献   

3.
Michael E. Palko 《CMAJ》1963,88(1):28-31
Thirty-two educational exhibits presented by the Ontario Medical Association at the 1961 Canadian National Exhibition in Toronto in the exhibit known as “Mediscope 1961” were subjected to an evaluative study. Applying the criteria of educational effectiveness to each exhibit, relative ratings for each exhibit as well as the educational value of Mediscope as a whole were obtained. Quantitative data indicated that this venture in health education was a highly successful endeavour, as 80% of the criteria for educational effectiveness were met by all exhibits. In addition, the study emphasized the potential of educational exhibits in the field of public health education as well as education of specific groups.The desirability of similar studies is stressed. In addition to quantitative assessment of educational exhibits, such studies would disclose the impact of health information on the attitudes and behavioural changes on the part of the public.  相似文献   

4.
S. Falkland 《CMAJ》1963,88(21):1084-1091
Available statistics were studied to define the extent of the lung cancer problem in Canada. Because of the low overall survival in treated and untreated cases at one year, mortality figures provide a rough index of morbidity from this disease.Male lung cancer death rates rose steadily from 3.0 to 24.6, and female rates from 1.6 to 4.0 per 100,000 population between 1931 and 1961. In males, the greatest increase occurred in the 70-74 year age group (eighteen-fold) and in females in the 80-84 year age group (seven-fold).Lung cancer caused 2774 deaths in Canada in 1961, and was the leading cause of cancer deaths for males in all age groups from 40 to 79 years. It accounted for approximately 1 in 5 of all cancer deaths in males and 1 in 26 in females.Lung cancer mortality in Canada has not increased to the same extent as in certain other countries, but to counter the rising trend, changes in the smoking habits of the population are required as well as community and industrial control of atmospheric carcinogens.  相似文献   

5.
气候变化与太湖蓝藻暴发的关系   总被引:14,自引:0,他引:14  
对太湖区域40多年来气温、降水量、日照时数随时间变化的特征进行了分析,并对太湖蓝藻的爆发时间、次数、等级进行了统计,采用对比分析法对气候变化与太湖蓝藻暴发的关系进行了分析。结果表明:太湖区域1961—2007年总的气候倾向率,年平均气温为0.35℃.10a-1,年累计降水量为31.33mm.10a-1,年累计日照时数为-69.00h.10a-1;而突变点,气温在1989年,降水量在1979年,日照时数在1999年,在突变点年份后,气温升高、降水量增加和日照时数减少的趋势更加明显。2000—2007年气候变得异常,主要表现为气温上升速度加快,约为1961—2007年的3.7倍,5月和10月的这种气候倾向性更明显;降水量减少,比1961—2007年减少了178.10mm.10a-1,日照时数增加,比1961—2007年增加了244.23h.10a-1。气候变暖速度加快为太湖蓝藻的生长发育提供了热量条件;降水量减少,加速了太湖水质恶化,为蓝藻暴发提供了有利的水质环境条件;日照时数增多,充足的光照为蓝藻生长发育提供了优良的光合条件;温度偏高、降水量偏少、日照时数偏多的气候变化趋势对应太湖蓝藻暴发的次数也偏多,造成了太...  相似文献   

6.
In this paper we examine the decline in mortality rates by cause of death in U.S. cities during the last decade of the. 19th century. Causes of death are grouped according to their probable relationship to specific public health measures. The reduction which occurred in the death rates from some diseases, e.g., typhoid and diarrheal diseases, can probably be attributed in part to the provision of sewers and waterworks. Large declines also occurred in the death rates from tuberculosis and diphtheria, but the relationship between the declines in these diseases and public health practices designed to combat them is more ambiguous. We therefore conclude that public health measures had some impact on the decline in mortality, but that these measures do not provide a complete explanation of the mortality decline.The research on which this paper is based was supported by NICHD Grant 1-R01-HD-05427. A version of this article was presented at the meetings of the American Sociological Association, New York, August 30–September 3, 1976.  相似文献   

7.
This study uses individual-level longitudinal data from Iceland, a country that experienced a severe economic crisis in 2008 and substantial recovery by 2012, to investigate the extent to which the effects of a recession on health behaviors are lingering or short-lived and to explore trajectories in health behaviors from pre-crisis boom, to crisis, to recovery. Health-compromising behaviors (smoking, heavy drinking, sugared soft drinks, sweets, fast food, and tanning) declined during the crisis, and all but sweets continued to decline during the recovery. Health-promoting behaviors (consumption of fruit, fish oil, and vitamins/minerals and getting recommended sleep) followed more idiosyncratic paths. Overall, most behaviors reverted back to their pre-crisis levels or trends during the recovery, and these short-term deviations in trajectories were probably too short-lived in this recession to have major impacts on health or mortality. A notable exception is for binge drinking, which declined by 10% during the 2 crisis years, continued to fall (at a slower rate of 8%) during the 3 recovery years, and did not revert back to the upward pre-crisis trend during our observation period. These lingering effects, which directionally run counter to the pre-crisis upward trend in consumption and do not reflect price increases during the recovery period, suggest that alcohol is a potential pathway by which recessions improve health and/or reduce mortality.  相似文献   

8.
根据呼伦湖流域1961—2010年的气温、降水、蒸发量资料以及1961—2008年径流量资料,利用非参数检验Mann-Kendall法,分析了近50年呼伦湖流域气候变化特征及其对流域径流量的影响。结果表明:呼伦湖流域近50年来气温整体呈显著上升趋势;年降水量受夏季降水量影响最为明显,经历了1961—1964年的上升,1964—1983年的下降,1983—2003年的上升和2003—2010年下降4个阶段;年蒸发量在1973年以前相对平稳,1973—1998年呈下降趋势,1999—2005年呈显著上升趋势,2005年为突变点,出现从高到低突变。夏、秋季节蒸发量趋势在时间段上与夏季降水量有很好的对应关系;径流量基本表现为1961—1965年偏丰,1965—1987年偏枯,其中1975—1980年间表现为显著下降趋势(P<0.05),1987—2002年偏丰,2002—2008年偏枯;在气温普遍升高的前提下,降水量整体呈减少趋势,其变化趋势在很大程度上决定蒸发量的变化,呼伦湖流域暖干化趋势显著。以径流自身的变化特征为时段划分基础,对比径流、气温、降水量和蒸发量的变化过程,经相关统计分析检验,发现夏、秋季气温、降水量和蒸发量是引起呼伦湖流域径流量变化的根本原因。  相似文献   

9.
In the summer of 1979–80, there was a sharp decline in the koala population along Mungalalla Creek in south-western Queensland. The decline was associated with a heatwave and drought. Live animals and carcasses were counted soon after the decline and at three subsequent periods. It was estimated that more than 63% of the population died. The drought and heatwave caused extensive leaf-fall and/or browning of the foliage in food trees along stretches of dry creek. The proximate cause of death was thought to be a combination of malnutrition and dehydration. There was evidence, including the differential survival of koalas along the creek, of marked heterogeneity in the quality of the habitat. At sites where the trees were not affected (mainly on large permanent water-holes) koalas had good body condition and mortality was low, whereas on stretches of dry creek (marginal habitat), koalas were in poor health (poor condition, anaemia, high tick loads) and mortality was very high. Survival of the population was not threatened because many animals survived at the permanent water-holes. There is evidence that mortality was highest among young animals which may be excluded from optimal sites by older dominant animals. In the years after the crash, continuing drought appeared to prevent recovery of the population. It is thought that such population crashes are rare events as they are apparently caused partly by unusual climatic conditions.  相似文献   

10.

Objective

This study investigated the trends in incidence and mortality of out-of-hospital cardiac arrest (OHCA), as well as factors associated with OHCA outcomes in Taiwan.

Methods

Our study included OHCA patients requiring cardiopulmonary resuscitation (CPR) upon arrival at the hospital. We used national time-series data on annual OHCA incidence rates and mortality rates from 2000 to 2012, and individual demographic and clinical data for all OHCA patients requiring mechanical ventilation (MV) care from March of 2010 to September of 2011. Analytic techniques included the time-series regression and the logistic regression.

Results

There were 117,787 OHCAs in total. The overall incidence rate during the 13 years was 51.1 per 100,000 persons, and the secular trend indicates a sharp increase in the early 2000s and a decrease afterwards. The trend in mortality was also curvilinear, revealing a substantial increase in the early 2000s, a subsequent steep decline and finally a modest increase. Both the 30-day and 180-day mortality rates had a long-term decreasing trend over the period (p<0.01). For both incidence and mortality rates, a significant second-order autoregressive effect emerged. Among OHCA patients with MV, 1-day, 30-day and 180-day mortality rates were 31.3%, 75.8%, and 86.0%, respectively. In this cohort, older age, the female gender, and a Charlson comorbidity index score ≥ 2 were associated with higher 180-day mortality; patients delivered to regional hospitals and those residing in non-metropolitan areas had higher death risk.

Conclusions

Overall, both the 30-day and the 180-day mortality rates after OHCA had a long-term decreasing trend, while the 1-day mortality had no long-term decline. Among OHCA patients requiring MV, those delivered to regional hospitals and those residing in non-metropolitan areas tended to have higher mortality, suggesting a need for effort to further standardize and improve in-hospital care across hospitals and to advance pre-hospital care in non-metropolitan areas.  相似文献   

11.

Background

A decline in the national maternal mortality ratio in Nepal has been observed from surveys conducted between 1996 and 2008. This paper aims to assess the plausibility of the decline and to identify drivers of change.

Methods

National and sub-national trends in mortality data were investigated using existing demographic and health surveys and maternal mortality and morbidity surveys. Potential drivers of the variation in maternal mortality between districts were identified by regressing district-level indicators from the Nepal demographic health surveys against maternal mortality estimates.

Results

A statistically significant decline of the maternal mortality ratio from 539 maternal deaths to 281 per 100,000 (95% CI 91,507) live births between 1993 and 2003 was demonstrated. The sub-national changes are of similar magnitude and direction to those observed nationally, and in the terai region (plains) the differences are statistically significant with a reduction of 361 per 100,000 live births (95% CI 36,686) during the same time period.The reduction in fertility, changes in education and wealth, improvements in components of the human development index, gender empowerment and anaemia each explained more than 10% of the district variation in maternal mortality. A number of limitations in each of the data sources used were identified. Of these, the most important relate to the underestimation of numbers of deaths.

Conclusion

It is likely that there has been a decline in Nepal''s maternal mortality since 1993. This is good news for the country''s sustained commitments in this area. Conclusions on the magnitude, pattern of the change and drivers of the decline are constrained by lack of data. We recommend close tracking of maternal mortality and its determinants in Nepal, attention to the communication of future estimates, and various options for bridging data gaps.  相似文献   

12.
Indirect estimates of maternal mortality in India indicate that fertility decline has reduced maternal deaths by reducing the frequency of pregnancy and childbirth. The earlier stages of fertility decline are also likely to have lowered maternal mortality by reducing the risk of pregnancy and childbirth as the proportion of births among risky multiparous, older women declines. However, further fertility decline may well be associated with some increase in risk. Risk will also remain high if the health status of Indian girls and women remains poor. This study uses a sample of maternal deaths and deliveries among patients who survived which occurred in Civil Hospital, Ahmedabad, Gujarat during 1982-1993 to investigate these issues further. The women in the sample have relatively low fertility and represent a fairly late stage of fertility decline. They also have persistently poor health status. Logit regression analysis reveals that although fertility decline is associated with some increase in risk, poor health status is the more important maternal mortality risk factor. Without attention to female health, even childbearing among expectant mothers with low fertility continues to be hazardous.  相似文献   

13.
藏北牧区地表湿润状况对气候变化的响应   总被引:8,自引:0,他引:8  
杜军  边多  胡军  拉巴  周刊社 《生态学报》2009,29(5):2437-2444
利用1961~2006年藏北牧区6个站月平均最高气温、最低气温、降水量、风速、相对湿度、日照时数资料,应用Penman-Monteith模型计算得出潜在蒸散,分析了地表湿润指数的变化趋势、年代际变化特征及季节差异,并讨论了影响地表湿润指数的气象因子.研究表明:近46a藏北牧区年地表湿润指数呈现增大趋势,增幅0.01~0.05/10a;四季地表湿润指数大部分牧区也呈增大趋势,春、秋季增幅明显.近26a(1981~2006年)、季潜在蒸散表现为明显的减少趋势,降水量显现增多趋势,地表湿润指数增大趋势加大,以夏季最为突出.就年平均而言,藏北牧区20世纪60年代初、中期以高湿低温为其主要气候特征;20世纪60年代后期至80年代中期,表现为冷干型的气候特征;90年代初之后,气温持续升高,地表湿润指数显著增加,呈现以暖湿为主的年代际变化特征.湿润指数对降水量、相对湿度和气温日较差的响应最为敏感,而对日照时数和风速的响应也较为明显.  相似文献   

14.
The aim of this paper was to analyse the regional variations and trends in mortality from cardiovascular diseases in the population aged 0-64 years in Dalmatia and Slavonia, over the period 1998 to 2009. Mortality data were derived from Central Bureau of Statistics. The results show that age-standardized mortality rates from total cardiovascular diseases, ischaemic heart diseases and cerebrovascular diseases were lower in Dalmatia than rates for Slavonia, for both genders. All mortality rates, except rates for ischaemic heart diseases mortality for men in both regions, showed the trend of decline. Dalmatia has a more protective factors in pattern of Mediterranean diet. The improvement of cardiovascular health and reduction of premature mortality from cardiovascular diseases requires a system and comprehensive intervention approach at all levels of health care and multisectorial coordination.  相似文献   

15.
Child health is a central issue in the public policy agenda of developing countries. Several policies aimed at improving child health have been implemented over the years, with varying degrees of success. In Brazil, such policies have triggered a significant decline in infant mortality rates over the last 30 years. Despite this improvement, however, mortality rates are still high compared to international standards. Moreover, there is considerable imbalance across Brazilian municipalities suggesting that various policies should be adopted. We investigate the determinants of infant mortality at the municipal level and provide an analysis of the factors affecting child health at the individual level. To analyze the mortality rate, we estimate static and dynamic panel data models using four censuses covering the period from 1970 to 2000. The demand for child health, on the other hand, is addressed through a household decision model, estimated using anthropometric data from the 1996 Standard of Living Survey. The results obtained indicate that a rise in sanitation, education and per capita income contributed to the decline of infant mortality in Brazil, with stronger impacts in the long run than in the short run. The fixed effects associated with county characteristics explain the observed dispersion in child mortality rates. The results from the decision model are confirmed by the findings of the mortality model: education, sanitation and poverty are the most important causes of poor child health in Brazil.  相似文献   

16.

Background

Coronary Heart Disease (CHD) is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey.

Methods and Findings

Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG) over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy). All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30%) resulted in estimated cost savings of $235,000,000 and 6455 LYG in Tunisia; $39,000,000 and 31674 LYG in Syria; $6,000,000 and 2682 LYG in Palestine and $1,3000,000,000 and 378439 LYG in Turkey.

Conclusion

Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives.  相似文献   

17.
Trends in mortality, nutritional status and food supply are compared to other living standard indicators for the Weimar Republic (1919-1933) and for the early years of the Nazi regime (1933-1937). The results imply that Germany experienced a substantial increase in mortality rates in most age groups in the mid-1930s, even relative to those of 1932, the worst year of the Great Depression. Moreover, children's heights--an indicator of the quality of nutrition and health--were generally stagnating between 1933 and 1938, but had increased significantly during the 1920s. Persecution, by itself, does not explain such an adverse development in biological welfare; the non-persecuted segments of the German population were affected as well. The reason for this adverse development was caused by the fact that military expenditures increased at the expense of public health measures. In addition, food imports were curtailed, and prices of many agricultural products were controlled. There is ample evidence that this set of economic policies had an adverse effect on the health and nutritional status of the population. The highly developed areas of Germany with large urban sectors and the coastal regions of the Northwest were affected most from the policy of restricting imports of protein-rich agricultural products.  相似文献   

18.

Objectives

The UK government has noted the public health importance of food prices and the affordability of a healthy diet. Yet, methods for tracking change over time have not been established. We aimed to investigate the prices of more and less healthy foods over time using existing government data on national food prices and nutrition content.

Methods

We linked economic data for 94 foods and beverages in the UK Consumer Price Index to food and nutrient data from the UK Department of Health''s National Diet and Nutrition Survey, producing a novel dataset across the period 2002–2012. Each item was assigned to a food group and also categorised as either “more healthy” or “less healthy” using a nutrient profiling model developed by the Food Standards Agency. We tested statistical significance using a t-test and repeated measures ANOVA.

Results

The mean (standard deviation) 2012 price/1000 kcal was £2.50 (0.29) for less healthy items and £7.49 (1.27) for more healthy items. The ANOVA results confirmed that all prices had risen over the period 2002–2012, but more healthy items rose faster than less healthy ones in absolute terms:£0.17 compared to £0.07/1000 kcal per year on average for more and less healthy items, respectively (p<0.001).

Conclusions

Since 2002, more healthy foods and beverages have been consistently more expensive than less healthy ones, with a growing gap between them. This trend is likely to make healthier diets less affordable over time, which may have implications for individual food security and population health, and it may exacerbate social inequalities in health. The novel data linkage employed here could be used as the basis for routine food price monitoring to inform public health policy.  相似文献   

19.
BACKGROUND: In October 2003 South Africa embarked on a program of folic acid fortification of staple foods. We measured the change in prevalence of NTDs before and after fortification and assessed the cost benefit of this primary health care intervention. METHODS: Since the beginning of 2002 an ecological study was conducted among 12 public hospitals in four provinces of South Africa. NTDs as well as other birth defect rates were reported before and after fortification. Mortality data were also collected from two independent sources. RESULTS: This study shows a significant decline in the prevalence of NTDs following folic acid fortification in South Africa. A decline of 30.5% was observed, from 1.41 to 0.98 per 1,000 births (RR = 0.69; 95% CI: 0.49–0.98; p = .0379). The cost benefit ratio in averting NTDs was 46 to 1. Spina bifida showed a significant decline of 41.6% compared to 10.9% for anencephaly. Additionally, oro‐facial clefts showed no significant decline (5.7%). An independent perinatal mortality surveillance system also shows a significant decline (65.9%) in NTD perinatal deaths, and in NTD infant mortality (38.8%). CONCLUSIONS: The decrease in NTD rates postfortification is consistent with decreases observed in other countries that have fortified their food supplies. This is the first time this has been observed in a predominantly African population. The economic benefit flowing from the prevention of NTDs greatly exceeds the costs of implementing folic acid fortification. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

20.
1970-79 US fertility trends among differnet racial, regional, age, educational, parity, and socioeconomic subgroups in the population were examined, using own children data from the 1976 Survey of Income and Education (SIE) and the March Current Population Surveys (CPS) from 1968-80. In addition, cross-sectional differences in fertility for the subgroups were compared for 1970 and 1976, using multiple regression analysis. 1st, the appropriateness of using fertility rates obtained from own children data was assessed by comparing fertility rates obtained from the SIE data with those derived from vital statistic and census data. The comparative analysis confirmed that the SIE data yielded an accurate estimate of period fertility rates for currently married women, provided the subgroup samples were sufficiently large. CPS fertility estimates were also judged to be accurate if data from 3 adjacent survey years was pooled to increase sample size. Fertility trends for 5 educational groups were assessed separately for 1967-73. During this periold, there was a marked decline in fertility for all 5 groups; for the group with 5-8 years of education the decline was only 14%, but for the other 4 groups, which included women with 9-16 or more years of education, the decline in fertility ranged from 26-29%. In assessing the 1970-76 trends, the sample was restricted to own children, aged 3 years or less, of currently married women, under 40 years of age. Among whites, there was an overall 20% decline in fertility between 1970-76 and an overall fertility increase of about 2% between 1976-79. These trends were observed in all 28 white subgroups. A similar pattern was observed for blacks. There was an overall fertility decline of 24% between 1970-76, and this decline was apparent for all subgroups except women with college degrees. Betwen 1976-79, black fertility rates, unlike white rates, continued to decline, but the rate of decline was only 3%. Furthermore, the decline in almost all the black subgroups was markedly less than in the 1970-76 periold, and for many of the subgroups the trend was reversed and fertility increased. In summary, the fertility trends noted for 1970-79 were pervasive for almost all the subgroups for both blacks and whites; i.e., there was a marked decline in fertility between 1970-76 and than a reversal or slowing down of the decline during the 1976-79 for all black and white subgroups. Cross-sectional fertility differences in the subgroups in 1970 and in 1979 were quite similar, and fertility rates differed markedly for the separate subgroups. These differences do not, of course, explain the pervasive trends observed in the analysis of the fertility rates over time. A similar study assessing fertility trends among subgroups for the early 1940's through the late 1960s also revealed the pervasive nature of period fertility trends. Demographers have not as yet been able to explain these shifts in fertility that cut across all subgroups in the US and which also characterize the period fertility rates in other developed countries. Tables provided information on 1) total fertility rates by educational level and by geographical region for 1945-1975; 2) % change in number of own children less than 3 years of age among women under age 40 by maternal age, maternal education, initial parity, geographical region, and husband's income; and 3) mean number of own children less than 3 years of age among women under age 40 by maternal age, education, parity, region, and husband's income.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号