Abstract:
:A few large multi-centre male-only heart trials done in the 1970s and 1980s have been seen as ill-conceived because they did not include females. The purpose here is to revisit two of those trials and to consider consequences in terms of cost and power had they been designed to include females.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Meinert CLdoi
10.1002/(sici)1097-0258(19990215)18:3<241::aid-simsubject
Has Abstractpub_date
1999-02-15 00:00:00pages
241-51; discussion 253-4issue
3eissn
0277-6715issn
1097-0258pii
10.1002/(SICI)1097-0258(19990215)18:3<241::AID-SIMjournal_volume
18pub_type
杂志文章abstract::In medical research, risk difference (RD) and number needed to treat (NNT) measures for survival times have been mainly proposed without consideration of covariates. In this paper, we develop adjusted RD and NNT measures for use in observational studies with survival time outcomes within the framework of the Cox propo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3793
更新日期:2010-03-30 00:00:00
abstract::Missing values in the covariates are a widespread complication in the statistical inference of regression models. The maximum likelihood principle requires specification of the distribution of the covariates, at least in part. For categorical covariates, log-linear models can be used. Additionally, the missing at rand...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780141205
更新日期:1995-06-30 00:00:00
abstract::While there has been extensive research developing gene-environment interaction (GEI) methods in case-control studies, little attention has been given to sparse and efficient modeling of GEI in longitudinal studies. In a two-way table for GEI with rows and columns as categorical variables, a conventional saturated int...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6281
更新日期:2014-12-20 00:00:00
abstract::Mediation analysis is a standard approach to understanding how and why an intervention works in social and medical sciences. However, the presence of missing data, especially missing not at random data, poses a great challenge for the applicability of this approach in practice. Current methods for handling such missin...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7413
更新日期:2017-11-10 00:00:00
abstract::Paired count data usually arise in medicine when before and after treatment measurements are considered. In the present paper we assume that the correlated paired count data follow a bivariate Poisson distribution in order to derive the distribution of their difference. The derived distribution is shown to be the same...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2382
更新日期:2006-06-15 00:00:00
abstract::The World Health Organization and collaborating institutions in four developing countries have conducted a multi-centre randomized controlled trial, in which clinics were allocated at random to two antenatal care (ANC) models. These were the standard 'Western' ANC model and a 'new' ANC model consisting of tests, clini...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/1097-0258(20010215)20:3<401::aid-sim801>3.
更新日期:2001-02-15 00:00:00
abstract::Mesothelioma is a rare cancer caused by exposure to asbestos. Belgium has a known long history of asbestos production, resulting in one of the highest mesothelioma mortality rates worldwide. While the production of asbestos has stopped completely, the long latency period of mesothelioma, which can fluctuate between 20...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8697
更新日期:2020-11-20 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100319
更新日期:1991-03-01 00:00:00
abstract::Ewell and Ibrahim derived the large sample distribution of the logrank statistic under general local alternatives. Their asymptotic results enable us to extend several group sequential designs which allow for early stopping in favour of the null hypothesis to the setting in which the cure rate model is appropriate. In...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20001130)19:22<3023::aid-sim638>
更新日期:2000-11-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4318
更新日期:2012-01-13 00:00:00
abstract::Correlation analysis is widely used in biomedical and psychosocial research for assessing rater reliability, precision of diagnosis and accuracy of proxy outcomes. The popularity of longitudinal study designs has propelled the proliferation in recent years of new methods for longitudinal and other multi-level clustere...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2857
更新日期:2007-09-30 00:00:00
abstract::Genetic markers can be used as instrumental variables, in an analogous way to randomization in a clinical trial, to estimate the causal relationship between a phenotype and an outcome variable. Our purpose is to extend the existing methods for such Mendelian randomization studies to the context of multiple genetic mar...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3843
更新日期:2010-05-30 00:00:00
abstract::When interpreting screening mammograms radiologists decide whether suspicious abnormalities exist that warrant the recall of the patient for further testing. Previous work has found significant differences in interpretation among radiologists; their false-positive and false-negative rates have been shown to vary widel...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2633
更新日期:2007-03-30 00:00:00
abstract::The analysis of repeated measures data can be conducted efficiently using a two-level random coefficients model. A standard assumption is that the within-individual (level 1) residuals are uncorrelated. In some cases, especially where measurements are made close together in time, this may not be reasonable and this ad...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780131605
更新日期:1994-08-30 00:00:00
abstract::The mutation and natural selection phenomenon can and often does cause the failure of antimicrobial, herbicidal, pesticide and cancer treatments selection pressures. This phenomenon operates in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6307
更新日期:2014-12-20 00:00:00
abstract::The need for resource-intensive laboratory assays to assess exposures in many epidemiologic studies provides ample motivation to consider study designs that incorporate pooled samples. In this paper, we consider the case in which specimens are combined for the purpose of determining the presence or absence of a pool-w...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4426
更新日期:2012-09-28 00:00:00
abstract::Prevalence data provided by cancer registries are generally biased, since the patients that were diagnosed before the starting of the registry's activity cannot be included in the statistics. The relevance of this incompleteness bias is estimated in this paper. Incidence and relative survival are modelled as parametri...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970228)16:4<425::aid-sim
更新日期:1997-02-28 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3865
更新日期:2010-05-20 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6906
更新日期:2016-07-10 00:00:00
abstract::A Non-Parametric Maximum Likelihood approach to the estimation of relative risks in the context of disease mapping is discussed and a NPML approximation to conditional autoregressive models is proposed. NPML estimates have been compared to other proposed solutions (Maximum Likelihood via Monte Carlo Scoring, Hierarchi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20000915/30)19:17/18<2539::aid-s
更新日期:2000-09-15 00:00:00
abstract::In this paper, an approach to estimating the cumulative mean function for history process with time dependent covariates and right censored time-to-event variable is developed using the combined technique of joint modeling and inverse probability weighting method. The consistency of proposed estimator is derived. Theo...
journal_title:Statistics in medicine
pub_type: 杂志文章
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8178
更新日期:2019-07-30 00:00:00
abstract::When the event time of interest depends on the censoring time, conventional two-sample test methods, such as the log-rank and Wilcoxon tests, can produce an invalid test result. We extend our previous work on estimation using auxiliary variables to adjust for dependent censoring via multiple imputation, to the compari...
journal_title:Statistics in medicine
pub_type: 杂志文章
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:2001-12-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2537
更新日期:2007-01-30 00:00:00
abstract::We discuss some of the fundamental concepts underlying the development of frailty and random effects models in survival. One of these fundamental concepts was the idea of a frailty model where each subject has his or her own disposition to failure, their so-called frailty, additional to any effects we wish to quantify...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1259
更新日期:2002-11-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780111202
更新日期:1992-09-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.719
更新日期:2001-04-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2000
更新日期:2005-02-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6584
更新日期:2015-12-20 00:00:00