Age patterns of mortality for older women: An analysis using the age‐specific rate of mortality change with age

The age‐specific rate of mortality change with age, defined by k(x) = d Inμ(x)/dx, where μ(x) is the age‐specific death rate at exact age x, is estimated for middle and old ages in ten selected populations that are considered to have relatively accurate age data. For females in each of the study populations, k(x) follows a bell‐shaped curve that usually peaks around age 75. In some of the populations, the age pattern of k(x) for males is confounded with substantial cohort variations, which seem to reflect long‐term impacts of their World War I experiences.

Among the mathematical models proposed by Gompertz, Makeham, Perks and Beard, only the Perks model is consistent with the bell‐shaped pattern of k(x). It is shown that, if the risk of death for every individual follows the Makeham equation and if the individual frailty is gamma‐distributed, then the age‐specific death rate follows the Perks equation.     

大剂量喹乙醇对建鲤生长和死亡率的影响

用添加不同剂量(150ppm、200ppm、300ppm、400ppm、500ppm、600ppm、800ppm、1000ppm)喹乙醇的颗粒饲料对建鲤(初重:70g左右)进行了为期63天的试验。结果表明:建鲤的平均尾增重以200—300ppm组最高;200ppm组耐低氧能力最强,半致死时间为3.27h,而且血糖含量最高,为215.94mg/100ml;600—1000ppm组出现中毒迹象:死亡率明显升高,最高达29.1％(1000ppm),耐低氧能力显著下降。     

The Navajo–U.S. Population Mortality Crossover since the Mid-20th Century

Mortality crossovers at older ages have been observed when comparing different populations, particularly disadvantaged populations with advantaged populations. A growing body of research indicates that mortality convergences to actual crossovers are real and not a result of overstating of age at the older ages. Only recently have the mortality experiences of Native Americans been compared with those of other Americans; specific Native American tribal populations have not been examined, however. Presented here are the mortality experiences of the Navajo and those of the total U.S. population and U.S. white population since the mid-20th century. Comparison provides further support to findings that convergences and crossovers actually occur between disadvantaged and advantaged populations.     

Tracing studies and analysis of the effect of loss to follow-up on mortality estimation from patient registry data

Summary. Before patient registries are used for studies of the long-term mortality that is associated with chronic medical conditions, the potential bias resulting from patients who become lost to follow-up must be investigated. A study design, used for a systemic lupus erythematosus patient registry, is described. The design involves tracing patients who are defined as 'lost to follow-up' according to specific criteria. This provides supplementary information on the mortality experience of patients who are lost to (regular) follow-up. Some methods of analysis are described, based on comparing the mortality experience of patients when under regular follow-up with the experience of patients after they are deemed to be lost to follow-up. The effect of loss to follow-up, death reporting and visits to the clinic on estimation procedures is illustrated and recommendations are made for patient registries which are to be used in mortality studies.     

The value of mortality risk reductions in Delhi,India

We interviewed commuters in Delhi, India, to estimate their willingness to pay (WTP) to reduce their risk of dying in road traffic accidents in three scenarios that mirror the circumstances under which traffic fatalities occur in Delhi. The WTP responses are internally valid: WTP increases with the size of the risk reduction, income, and exposure to road traffic risks, as measured by length of commute and whether the respondent drives a motorcycle. As a result, the value of a statistical life (VSL) varies across groups of beneficiaries. For the most highly-exposed individuals the VSL is about 150,000 Purchasing Power Parity (PPP) dollars.

Willingness to pay for mortality risk reductions: Does latency matter?

Using results from two contingent valuation surveys conducted in Canada and the U.S., we explore the effect of a latency period on willingness to pay (WTP) for reduced mortality risk using a structural model. We find that delaying the time at which the risk reduction occurs by 10 to 30 years reduces WTP by more than 60% for respondents in both samples aged 40 to 60 years. The implicit discount rates are equal to 3.0–8.6% for Canada and 1.3–5.6% for the U.S. JEL Classification Q51 · Q58 The findings, interpretations and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the USEPA or of the World Bank, its Executive Directors or the countries they represent.     

Changing causes of death and the sex differential in the USA

This paper examines the sex differential in US life expectancy, the changes in this differential over the past 25 years and into the near future, and the apportionment of these differences among the leading causes of death. Movements in the sex differential over the years 1960–1985 were largely determined by changes in the accidents and violence and heart disease causes of death. The use of the life expectancy measure emphasizes the importance of those causes of death that impact most severely at younger ages. The historical analysis is extended through projections of life expectancies by sex. In the projections increased cancer mortality among males contributes to a widening differential, tempered by greater progress against heart disease for males.This is a revised version of a paper presented at the meetings of the Population Association of America, 30 April-2 June 1992, in Denver, Colorado.     

中国老人丧偶与其死亡风险的关系分析——配偶照顾的作用

文章基于中国老人健康长寿影响因素研究数据(1998~2005),利用Cox比例风险模型考察了中国老人丧偶对其死亡风险的影响机制,并深入分析了配偶照顾因素在降低老人死亡风险中的作用。结果发现:丧偶与死亡风险具有显著的关系,一般而言,长期丧偶老人的死亡风险显著地高于长期有偶的老人。而且,除了高龄女性老人之外,老人在丧偶初期,其死亡风险会大大增加。在解释丧偶是如何影响老人的死亡风险时,配偶的照顾是一个非常重要的因素,在控制配偶照顾的条件下,丧偶者与有偶者的死亡风险差异会大幅下降,这说明来自配偶的生活照顾对于老人的寿命发挥着重要影响。此外,本研究也发现配偶照顾的作用具有显著的性别差异和年龄组差异。