Bias and precision of measures of survival gain from right‐censored data

In cost‐effectiveness analyses of drugs or health technologies, estimates of life years saved or quality‐adjusted life years saved are required. Randomised controlled trials can provide an estimate of the average treatment effect; for survival data, the treatment effect is the difference in mean survival. However, typically not all patients will have reached the endpoint of interest at the close‐out of a trial, making it difficult to estimate the difference in mean survival. In this situation, it is common to report the more readily estimable difference in median survival. Alternative approaches to estimating the mean have also been proposed. We conducted a simulation study to investigate the bias and precision of the three most commonly used sample measures of absolute survival gain – difference in median, restricted mean and extended mean survival – when used as estimates of the true mean difference, under different censoring proportions, while assuming a range of survival patterns, represented by Weibull survival distributions with constant, increasing and decreasing hazards. Our study showed that the three commonly used methods tended to underestimate the true treatment effect; consequently, the incremental cost‐effectiveness ratio (ICER) would be overestimated. Of the three methods, the least biased is the extended mean survival, which perhaps should be used as the point estimate of the treatment effect to be inputted into the ICER, while the other two approaches could be used in sensitivity analyses. More work on the trade‐offs between simple extrapolation using the exponential distribution and more complicated extrapolation using other methods would be valuable. Copyright © 2015 John Wiley & Sons, Ltd.     

Deprivation and Poverty in Hong Kong

Despite high and rising real incomes, the poverty rate in Hong Kong remains a cause of community concern. The government has been reluctant to set a poverty line, although the recently (re‐)established Commission on Poverty has recommended that a poverty line for Hong Kong is developed. Against this background, this article reports results derived from a new deprivation study designed to shed new light on the living standards of the poorest in the community. Reflecting international studies, deprivation is identified as existing when people do not have and cannot afford items regarded by a majority in the community as being essential for all. A list of 35 basic needs items is identified as meeting this definition, the results indicating that around 30 per cent are deprived of at least two items, over 18 per cent are deprived of at least four items and 10 per cent are deprived of at least eight items. Deprivation rates are particularly high among items that meet basic health needs. A mean deprivation score index (MDIS) is then used to compare the degree of deprivation experienced by different groups, and indicates that deprivation is most pronounced amongst those receiving Comprehensive Social Security Assistance (CSSA), people affected by a disability and recent migrants. The overlap between deprivation and income poverty is also relatively low, which suggests both measures have a role to play in identifying who is most vulnerable and guiding where policy change is most urgently needed.     

Perspectives on being a father from men involved with child welfare services

Fathers can make positive contributions to their children's well‐being. However, involving the literature and this research indicate that fathers are much less likely to be engaged with child welfare services than mothers. This paper reports the findings of life story research with 18 fathers involved with child welfare. It focuses on these men's perspectives of fatherhood and their relationships with their children. Also, reactions to these fatherhood stories from father and service provider focus groups are examined. The findings challenge common perceptions of these fathers and highlight similarities and differences in perspectives between fathers and service providers. Implications for engaging fathers in child welfare practice are discussed.     

Asymptotic Comparison Between Constant-stress Testing and Step-stress Testing for Type-I Censored Data from Exponential Distribution

By running the life tests at higher stress levels than normal operating conditions, accelerated life testing quickly yields information on the lifetime distribution of a test unit. The lifetime at the design stress is then estimated through extrapolation using a regression model. In constant-stress testing, a unit is tested at a fixed stress level until failure or the termination time point of the test, while step-stress testing allows the experimenter to gradually increase the stress levels at some pre-fixed time points during the test. In this article, the optimal k-level constant-stress and step-stress accelerated life tests are compared for the exponential failure data under Type-I censoring. The objective is to quantify the advantage of using the step-stress testing relative to the constant-stress one. A log-linear relationship between the mean lifetime parameter and stress level is assumed and the cumulative exposure model holds for the effect of changing stress in step-stress testing. The optimal design point is then determined under C-optimality, D-optimality, and A-optimality criteria. The efficiency of step-stress testing compared to constant-stress testing is discussed in terms of the ratio of optimal objective functions based on the information matrix.     

Cycles of Adaptive Strategies Over the Life Course

An increasing number of Australia’s ageing population are aging with long-term physical impairments. This study explored the life experiences of this group using a qualitative approach. In-depth interviews were conducted with 10 disabled Victorians, aged between 51 and 84 years, and an inductive thematic analysis undertaken. A relationship was found between the adaptive strategies that participants developed as they moved through life phases and the impairment stages. The implications of the emergence of a cyclical process of adaptation across the life course. and particularly in respect of aging, delivery of aged-care services and social workers in this sector are discussed.     

生命历程理论视角下劳动力迁移对初婚年龄的影响

本文利用2012年清华大学“城镇化与劳动力移民”项目的调查数据,通过事件史方法考察劳动力迁移对初婚年龄的影响。研究发现,劳动力迁移会对初婚年龄产生推迟效应,迁移事件发生的时机和过程都会左右这一影响的具体结果。研究显示,越早实现迁移,越有助于移民进入婚姻,频繁的流动则削弱了结婚的可能性,而父亲的迁移经历同样会对子女的初婚年龄产生影响。通过对不同世代群体的比较,本文进一步发现,迁移对初婚年龄的影响程度随世代推移呈现“倒U型”趋势,这一结果与不同世代下的迁移特点及其身处情境有关。研究结果表明,劳动力移民的生命历程基于迁移发生了转轨,他们放缓了自我再生产的周期,这对人口结构和社会结构的调整具有重大意义。     

基于企业生命周期的顾客满意度研究

借鉴弗农的“产品生命周期”思想,把同一企业经历的不同市场阶段(完全垄断市场、寡头垄断市场、垄断竞争市场、完全竞争市场)作为一个生命周期,利用企业生命周期的变更,分析在企业生命周期的不同阶段,顾客满意度和顾客忠诚度的变化、顾客满意度和顾客忠诚度之间的关系;并提出两种顾客满意度测评模型。     

反思与生命之光 --论黑格尔的辩证法及其形而上意境

论述了黑格尔反思式的概念辩证法所承载的形而上意境,及其两者之间一而二、二而一的关系.     

哈贝马斯《交往行动理论》中的一般与个别

哈贝马斯在<交往行动理论>中,把交往理性与工具理性、生活世界与系统、交往行动与目的行动、交往语言与独白语言作了厘清,阐述了<交往行动理论>构建出的社会批判理论体系.在这一体系中,交往行动理论是其精髓.根据交往行动理论,他构建了一个公正世界的"乌托邦".     

论苏曼殊小说的悲剧意识

苏曼殊小说所描写的都是爱情悲剧,并带有明显的主观抒情色彩和自传性质,作家内心深处强烈的悲剧意识支配着他的小说情节的发展,是导致爱情悲剧的根本原因。这种悲剧意识既源于作家深受佛教观念的影响而产生的情思与佛礼之间的挣扎,也根源于作家由特殊身世而产生的认定人生本苦的生命意识。