Statistics for weighing benefits and harms in a proposed genetic substudy of a randomized cancer prevention trial

Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.     

MODEL-ASSISTED HIGHER-ORDER CALIBRATION OF ESTIMATORS OF VARIANCE

In survey sampling, interest often centres on inference for the population total using information about an auxiliary variable. The variance of the estimator used plays a key role in such inference. This study develops a new set of higher‐order constraints for the calibration of estimators of variance for various estimators of the population total. The proposed strategy requires an appropriate model for describing the relationship between the response and auxiliary variable, and the variance of the auxiliary variable. It is therefore referred to as a model‐assisted approach. Several new estimators of variance, including the higher‐order calibration estimators of the variance of the ratio and regression estimators suggested by Singh, Horn & Yu and Sitter & Wu are special cases of the proposed technique. The paper presents and discusses the results of an empirical study to compare the performance of the proposed estimators and existing counterparts.     

英汉习语的文化翻译

由于文化背景的不同,英汉两种语言的习语文化内涵也有差异。该文先从思维方式、风俗习惯、宗教神话和地域环境四方面讨论了英汉习语文化内涵的不同,然后分析了引起习语翻译障碍的原因,依据等效翻译理论对习语翻译的方法作了简要探讨。     

宋代绍兴城镇发展简论

宋代绍兴地区城镇已得到初步发展 ,并呈现出城市化趋势 ,其原因是社会经济发展、人口增长和交通发达。这一时期城镇的发展 ,无论是数量、规模 ,还是经济发展状况、市镇管理等 ,均居于浙江地区的前列 ,为明清时期的进一步繁荣奠定了基础。但各地城镇的发展又是不平衡的 ,显示了一定的地区差异 ,并从城镇居民的生活中 ,反映出社会的贫富现象。     

论科技期刊的品牌资本

科技期刊的品牌资本是其生存和发展的关键因素,品牌资本体现了社会效益与经济效益的同一性。品牌资本的价值回归是一个缓慢但却是相当稳定的过程。通过抽样调查和方差分析,定量说明了上述论点的正确性。     

汉英文化差异与大学英语教学研究

文化和语言是密不可分的,语言是一种社会文化现象,是社会文化发展的产物.任何语言的生存和发展都离不开赖以生存的社会文化环境,社会文化又在一定程度上制约着语言使用者的思维和表达能力.文章通过对汉英文化差异在语言学各个层次上的表现,以及英美文化背景知识对汉英文化影响的探讨,提出英美文化导入在大学英语教学中的方式方法.     

Young helpline callers and difference: exploring gender, ethnicity and sexuality in helpline access and provision

This article, which has its origin in a feasibility study carried out for three youth telephone helplines, focuses on gender, difference and helpline access by young people. During the research process the writers noted that for the three commissioning helplines, as is the case with the majority of other telephone helplines, approximately two‐thirds of callers are female. A helpline for young Muslims where the gender access ratio was 50/50 stood out as being different in this respect. Until recently, literature on gender and help‐seeking has tended towards making a blanket identification of males as experiencing difficulties in negotiating pathways to help. Although this difficulty of males is evident in relation to both help‐seeking and access to helplines, our study suggests that, at least in relation to helpline usage, when we take culture, ethnicity and sexuality into account, the help‐seeking situation may be more nuanced. This has implications in terms of enabling a cross‐section of young people to access helplines as well as with regard to helpline service development.     

马寅初的人口质量观及其现实意义——纪念马寅初诞辰120周年

注重人口质量是马寅初人口思想对马尔萨斯人口论的实质性超越.马寅初关于人口质量的观点主要体现于:人口质量与人口数量是对立的统一;在新时代,人不在乎多,而在乎精;人口质量的提高是德、智、体全面的提高和全民的提高;提高人口质量不能离开本国国情.在现代化进程中我们重温马寅初关于提高人口质量方面的有关观点和主张,有助于我们处理好提高人口质量与稳定低生育水平、保护资源环境、提高农民收入等方面的关系.     

On pooling data summaries in the absence of interactions “response-by-study”

The standard hypothesis testing procedure in meta-analysis (or multi-center clinical trials) in the absence of treatment-by-center interaction relies on approximating the null distribution of the standard test statistic by a standard normal distribution. For relatively small sample sizes, the standard procedure has been shown by various authors to have poor control of the type I error probability, leading to too many liberal decisions. In this article, two test procedures are proposed, which rely on thet—distribution as the reference distribution. A simulation study indicates that the proposed procedures attain significance levels closer to the nominal level compared with the standard procedure.