Abstract:
:This paper investigates the Bayesian procedures for comparing proportions. These procedures are especially suitable for accepting (or rejecting) the equivalence of two population proportions. Furthermore the Bayesian predictive probabilities provide a natural and flexible tool in monitoring trials, especially for choosing a sample size and for conducting interim analyses. These methods are illustrated with two examples where antithrombotic treatments are administrated to prevent further occurrences of thromboses.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Lecoutre B,Derzko G,Grouin JMdoi
10.1002/sim.4780140924subject
Has Abstractpub_date
1995-05-15 00:00:00pages
1057-63; discussion 1064issue
9-10eissn
0277-6715issn
1097-0258journal_volume
14pub_type
杂志文章abstract::Conditional power and predictive power provide estimates of the probability of success at the end of the trial based on the information from the interim analysis. The observed value of the time to event endpoint at the interim analysis could be biased for the true treatment effect due to early censoring, leading to a ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7673
更新日期:2018-08-15 00:00:00
abstract::We consider the problem of comparing cumulative incidence functions of non-mortality events in the presence of informative coarsening and the competing risk of death. We extend frequentist-based hypothesis tests previously developed for non-informative coarsening and propose a novel Bayesian method based on comparing ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3397
更新日期:2008-12-10 00:00:00
abstract::This paper describes statistical procedures for use in an experiment that compares two handwashing protocols. The evaluation of a handwashing protocol entails collection of the wash effluent. Colony counts for the effluent reflect the number of flora removed by the wash protocol. The analysis aims to formulate and est...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/sim.4780050412
更新日期:1986-07-01 00:00:00
abstract::In this paper we study the problem of variable selection for the proportional odds model, which is a useful alternative to the proportional hazards model and might be appropriate when the proportional hazards assumption is not satisfied. We propose to fit the proportional odds model by maximizing the marginal likeliho...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2833
更新日期:2007-09-10 00:00:00
abstract::In a cluster randomized cross-over trial, all participating clusters receive both intervention and control treatments consecutively, in separate time periods. Patients recruited by each cluster within the same time period receive the same intervention, and randomization determines order of treatment within a cluster. ...
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::The Jimma Infant Survival Differential Longitudinal Study is an Ethiopian study, set up to establish risk factors affecting infant survival and to investigate socio-economic, maternal and infant-rearing factors that contribute most to the child's early survival. Here, a subgroup of about 1500 children born in Jimma to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990415)18:7<835::aid-sim
更新日期:1999-04-15 00:00:00
abstract::Maps of estimated disease rates over multiple time periods are useful tools for gaining etiologic insights regarding potential exposures associated with specific locations and times. In this paper, we describe an extension of the Gangnon-Clayton model for spatial clustering to spatio-temporal data. As in the purely sp...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3984
更新日期:2010-09-30 00:00:00
abstract::The risk that a drug newly introduced into medical use will occasionally cause adverse reactions is neither negligible nor totally avoidable. Only well organized systems of monitoring can bring early detection and appropriate action. These in turn require either detailed supervision or spontaneous reporting. The paper...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780010208
更新日期:1982-04-01 00:00:00
abstract::Clinical studies that involve the recording of two or more distinct and well-defined events on each subject give rise to multiple event data. Treatment comparisons are usually reported in univariate analyses of time to first event or number of events observed. However, this approach may not uncover the 'full story' of...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1002/(sici)1097-0258(19970430)16:8<941::aid-sim
更新日期:1997-04-30 00:00:00
abstract::Elevated plasma levels of apolipoproteins A1 (apoA1) and B (apoB) are important protective factors and risk factors, respectively, for atherosclerosis and coronary heart disease. It is well known that both apoA1 and apoB reveal strong familial aggregation. Our goal was to investigate whether exogenous variables influe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20001230)19:24<3345::aid-sim829>
更新日期:2000-12-30 00:00:00
abstract::Regression to the mean arises often in statistical applications where the units chosen for study relate to some observed characteristic in the extreme of its distribution. Gardner and Heady attribute the effect of regression to the mean to measurement errors. They assume the model Yi = U + ei, where U is a fixed withi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100812
更新日期:1991-08-01 00:00:00
abstract::The problem for assessing biosimilarity and drug interchangeability of follow-on biologics (biosimilar products) is studied. Unlike the generic products, the development of biosimilar products is much more complicated because of fundamental differences in functional structures and manufacturing processes. As a result,...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5571
更新日期:2013-02-10 00:00:00
abstract::The sample size required for a cluster randomised trial is inflated compared with an individually randomised trial because outcomes of participants from the same cluster are correlated. Sample size calculations for longitudinal cluster randomised trials (including stepped wedge trials) need to take account of at least...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7028
更新日期:2016-11-20 00:00:00
abstract::In epidemiological studies we often want to learn about the direct effect of an exposure on an outcome, i.e. the effect that is not relayed by a specific intermediate variable. In the literature, there are two common definitions of direct effects; controlled and natural. When the intermediate variable and the outcome ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3493
更新日期:2009-02-15 00:00:00
abstract::Correlation is always a concern in the analysis of clustered data. One area of interest is to develop a general correlation modelling approach for high dimensional data with unbalanced hierarchical and heterogeneous data structures, e.g. multilevel data. Commonly used correlation structures might have limitation for s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2368
更新日期:2006-07-30 00:00:00
abstract::An observed confidence distribution is proposed as a measure of strength of evidence for practically equivalent efficacies of two treatments. The concept is independent of prior opinions about relevant sizes of a difference in efficacy. It also avoids retrospective power calculations for trials with missed recruitment...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780071207
更新日期:1988-12-01 00:00:00
abstract::Growth trends in children are often based on cross-sectional studies, in which a sample of the population is investigated at one given point in time. Estimating age-related percentiles in such studies involves fitting data distributions, each of which is specific for one age group, and a subsequent smoothing of the pe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000315)19:5<697::aid-sim
更新日期:2000-03-15 00:00:00
abstract::This paper concerns using modified weighted Schoenfeld residuals to test the proportionality of subdistribution hazards for the Fine-Gray model, similar to the tests proposed by Grambsch and Therneau for independently censored data. We develop a score test for the time-varying coefficients based on the modified Schoen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5815
更新日期:2013-09-30 00:00:00
abstract::A problem occurring in chronic disease modeling is the estimation of transition probabilities of moving from one state of a categorical risk factor to another. Transitions could be obtained from a cohort study, but often such data may not be available. However, under the assumption that transitions remain stable over ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4423
更新日期:2012-03-15 00:00:00
abstract::In this paper, we discuss family-based association test (FBATs) relating genetic data to survival and time-to-onset data. We show how the standard logrank and Wilcoxon statistics can be used with family data to develop tests of association. We prove that the FBAT-logrank approach can be identical to the proportional h...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1707
更新日期:2004-01-30 00:00:00
abstract::We develop analysis methods for clinical trials with time-to-event outcomes which correct for treatment changes during follow-up, yet are based on comparisons of randomized groups and not of selected groups. A causal model relating observed event times to event times that would have been observed under other treatment...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19991015)18:19<2617::aid-s
更新日期:1999-10-15 00:00:00
abstract::We investigate population-averaged (PA) and cluster-specific (CS) associations for clustered binary logistic regression in the context of a longitudinal clinical trial that investigated the association between tooth-specific visual elastase kit results and periodontal disease progression within 26 weeks of follow-up. ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780140407
更新日期:1995-02-28 00:00:00
abstract::We use a mixed Poisson regression model with extra variation to analyse mortality data cross-classified by age and geographic region. We use estimates of dispersion parameter and fixed effects parameters, obtained by maximizing a marginal quasi-likelihood function, to estimate mortality rates in an empirical Bayes man...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19960715)15:13<1397::AID-S
更新日期:1996-07-15 00:00:00
abstract::Nutritional exposures are often measured with considerable error in commonly used surrogate instruments such as the food frequency questionnaire (FFQ) (denoted by Q(i) for the ith subject). The error can be both systematic and random. The diet record (DR) denoted by R(i) for the ith subject is considered an alloyed go...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3238
更新日期:2008-08-15 00:00:00
abstract::The two-period cross-over design with two sequences of drug administration is a standard experimental design when bioequivalence of one test formulation is to be assessed in comparison with a reference formulation. Previously, an approach based on Fieller's confidence interval has been presented for the assessment of ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19971015)16:19<2229::aid-s
更新日期:1997-10-15 00:00:00
abstract::With increasingly abundant spatial data in the form of case counts or rates combined over areal regions (eg, ZIP codes, census tracts, or counties), interest turns to formal identification of difference "boundaries," or barriers on the map, in addition to the estimated statistical map itself. "Boundary" refers to a bo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7408
更新日期:2017-11-10 00:00:00
abstract::In England and Wales, a large-scale multiple statistical surveillance system for infectious disease outbreaks has been in operation for nearly two decades. This system uses a robust quasi-Poisson regression algorithm to identify abberrances in weekly counts of isolates reported to the Health Protection Agency. In this...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5595
更新日期:2013-03-30 00:00:00
abstract::To update the British growth reference, anthropometric data for weight, height, body mass index (weight/height2) and head circumference from 17 distinct surveys representative of England, Scotland and Wales (37,700 children, age range 23 weeks gestation to 23 years) were analysed by maximum penalized likelihood using ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:
更新日期:1998-02-28 00:00:00
abstract::Non-linear mixed-effects models (NLMEMs) are used to improve information gathering from longitudinal studies and are applied to treatment evaluation in disease-evolution studies, such as human immunodeficiency virus (HIV) infection. The estimation of parameters and the statistical tests are critical issues in NLMEMs s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2950
更新日期:2007-11-30 00:00:00
abstract::Disease incidence predictions are useful for a number of administrative and scientific purposes. The simplest ones are made using trend extrapolation, on either an arithmetic or a logarithmic scale. This paper shows how approximate confidence prediction intervals can be calculated for such predictions, both for the to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780131503
更新日期:1994-08-15 00:00:00