Abstract:
:Graphical methods are often used to check goodness-of-fit of models to data. It is common to plot residuals against a reference distribution so that when the model fits the data, the configuration should be close to a straight line. Since the resemblance to a straight line is often unclear, it has been suggested to add simulated envelopes within which the configuration is expected to lie. The implementation of this method for survival data analysis is not straightforward. In this paper we point out the difficulties which arise in constructing envelopes on residual plots for randomly censored data. Methods are suggested to deal with the problems and evaluated; they are illustrated by simulated data and on a follow-up study of myeloma.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Cohen A,Barnett Odoi
10.1002/sim.4780141607subject
Has Abstractpub_date
1995-08-30 00:00:00pages
1785-95issue
16eissn
0277-6715issn
1097-0258journal_volume
14pub_type
杂志文章abstract::Various aspects of portfolio management and project prioritization within the pharmaceutical industry are examined. It is shown that the cost and probability architecture of a project is a crucial aspect of its value. An appropriate simple tool for ranking projects is the Pearson index. Various difficulties are consid...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19961230)15:24<2689::AID-S
更新日期:1996-12-30 00:00:00
abstract::This paper presents tables analogous to T-tables for use in the 2 x 2 multinomial trial, where the continuity corrected Z-statistic is used to make exact unconditional inference. This is the first solution of a discrete exact unconditional inference problem involving a multivariate nuisance parameter for which no anci...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780110708
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abstract::To study the spread of sexually transmitted diseases (STDs) using social/sexual mixing models, one must have quantitative information about sexual mixing. An unavoidable complication in gathering such information by survey is that members of the surveyed population will almost certainly have sexual contacts outside th...
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
abstract::Within the rich literature on generalized linear models, substantial efforts have been devoted to models for categorical responses that are either completely ordered or completely unordered. Few studies have focused on the analysis of partially ordered outcomes, which arise in practically every area of study, includin...
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::The use of the continual reassessment method (CRM) and other model-based approaches to design Phase I clinical trials has increased owing to the ability of the CRM to identify the maximum tolerated dose better than the 3 + 3 method. However, the CRM can be sensitive to the variance selected for the prior distribution ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5621
更新日期:2013-06-15 00:00:00
abstract::Many reactions in enzymology are governed by the Michaelis-Menten equation. Characterising these reactions requires the estimation of the parameters K(M) and V(max) which determine the Michaelis-Menten equation and this is done by observing rates of reactions at a set of substrate concentrations. The choice of substra...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1612
更新日期:2004-02-15 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
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3474
更新日期:2009-01-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000530)19:10<1319::aid-s
更新日期:2000-05-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2656
更新日期:2007-05-10 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3303
更新日期:2008-07-30 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::Laboratory determinations on children aged 6 to 10 years obtained over a 5-year period are analysed by a method described in detail for differentiating between children from exposed and control areas of Seveso, Italy. In the analysis, stratification is employed to distinguish the separate days of laboratory measuremen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780020221
更新日期:1983-04-01 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8056
更新日期:2019-04-30 00:00:00
abstract::The incremental life expectancy, defined as the difference in mean survival times between two treatment groups, is a crucial quantity of interest in cost-effectiveness analyses. Usually, this quantity is very difficult to estimate from censored survival data with a limited follow-up period. The paper develops estimati...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6951
更新日期:2016-09-10 00:00:00
abstract::The back-calculation method has been used to estimate the number of HIV infections from AIDS incidence data in a particular population. We present an extension of back calculation that provides estimates of the numbers of HIV infectives in different stages of infection. We model the staging process with a time-depende...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780110612
更新日期:1992-04-01 00:00:00
abstract::The identification of new adverse drug reactions is often tricky. For a given case, the relationship between drug exposure and symptom occurrence is usually questionable. It could be investigated statistically from a series of drug-event association cases with an independence test between the two variables. Analysing ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100621
更新日期:1991-06-01 00:00:00
abstract::Confounding is a major concern in observational studies. To adjust for confounding bias, the potential confounder(s) for a study must first be identified and measured. But this is not always possible. The unmeasured factors may also exhibit effect modification, and this further complicates the situation. In this paper...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4151
更新日期:2011-04-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000229)19:4<453::aid-sim
更新日期:2000-02-29 00:00:00
abstract::A mediator acts as a third variable in the causal pathway between a risk factor and an outcome. In this paper, we consider the estimation of the mediation effect when the mediator is a binary variable. We give a precise definition of the mediation effect and examine asymptotic properties of five different estimators o...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2730
更新日期:2007-08-15 00:00:00
abstract::In the development of a new treatment in oncology, phase II trials play a key role. On the basis of the data obtained during phase II, it is decided whether the treatment should be studied further. Therefore, the decision to be made on the basis of the data of a phase II trial must be as accurate as possible. For ethi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5585
更新日期:2012-12-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6138
更新日期:2014-07-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2204
更新日期:2006-07-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5683
更新日期:2013-06-30 00:00:00
abstract::Subjective judgements of complex variables are commonly recorded as ordered categorical data. The rank-invariant properties of such data are well known, and there are various statistical approaches to the analysis and modelling of ordinal data. This paper focuses on the non-additive property of ordered categorical dat...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981230)17:24<2923::aid-s
更新日期:1998-12-30 00:00:00
abstract::Randomized clinical trial designs commonly include one or more planned interim analyses. At these times an external monitoring committee reviews the accumulated data and determines whether it is scientifically and ethically appropriate for the study to continue. With failure-time endpoints, it is common to schedule an...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.843
更新日期:2001-07-30 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::We propose the use of Gaussian mixed models to analyse statistically 24 hour ambulatory blood pressure data from clinical trials. We develop specific models and apply them to data from a clinical study that compares two angiotensin-converting enzyme inhibitors. We investigate and discuss computing issues related to th...
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.4780121803
更新日期:1993-09-30 00:00:00
abstract::Medical costs data with administratively censored observations often arise in cost-effectiveness studies of treatments for life-threatening diseases. Mean of medical costs incurred from the start of a treatment until death or a certain time point after the implementation of treatment is frequently of interest. In many...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1556
更新日期:2004-11-15 00:00:00
abstract::Sexually transmitted infections (STIs) with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis are among the most common infectious diseases in the United States, disproportionately affecting young women. Because a significant portion of the infections present no symptoms, infection control relies...
journal_title:Statistics in medicine
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