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 Schoenfeld residuals derived assuming a certain form of non-proportionality. The methods perform well in simulations and a real data analysis of breast cancer data, where the treatment effect exhibits non-proportional hazards.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Zhou B,Fine J,Laird Gdoi
10.1002/sim.5815subject
Has Abstractpub_date
2013-09-30 00:00:00pages
3804-11issue
22eissn
0277-6715issn
1097-0258journal_volume
32pub_type
杂志文章abstract::We analyse the effect of using prevalence rates based on populations with different sizes in the power of spatial independence tests. We compare the well known spatial correlation Moran's index to three indexes obtained after adjusting for population density, one proposed by Oden, another proposed by Waldhör, and a th...
journal_title:Statistics in medicine
pub_type: 杂志文章
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journal_title:Statistics in medicine
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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
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journal_title:Statistics in medicine
pub_type: 杂志文章
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journal_title:Statistics in medicine
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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
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更新日期:2017-11-10 00:00:00
abstract::The 'at least as good as' criterion, introduced by Laster and Johnson for a continuous response variate, is developed here for applications with dichotomous data. This approach is adaptive in nature, as the margin of non-inferiority is not taken as a fixed difference; it varies as a function of the positive control re...
journal_title:Statistics in medicine
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journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:Statistics in medicine
pub_type: 杂志文章
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abstract::Studies based on aggregated hospital outcome data have established that there is a relationship between nurse staffing and adverse events. However, this result could not be confirmed in Belgium where 96 per cent of the variability of nurse staffing levels over nursing units (belonging to different hospitals) is explai...
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.5683
更新日期:2013-06-30 00:00:00
abstract::Machine learning techniques such as classification and regression trees (CART) have been suggested as promising alternatives to logistic regression for the estimation of propensity scores. The authors examined the performance of various CART-based propensity score models using simulated data. Hypothetical studies of v...
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1868
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5916
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000430)19:8<1059::aid-si
更新日期:2000-04-30 00:00:00
abstract::Missing data arise in crossover trials, as they do in any form of clinical trial. Several papers have addressed the problems that missing data create, although almost all of these assume that the probability that a planned observation is missing does not depend on the value that would have been observed; that is, the ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4497
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8698
更新日期:2020-11-20 00:00:00
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:2009-10-30 00:00:00
abstract::For the meta-analysis of controlled clinical trials with binary outcome a test statistic for testing an overall treatment effect is proposed, which is based on a refined estimator for the variance of the treatment effect estimator usually used in the random-effects model of meta-analysis. In simulation studies it is s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1009
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7065
更新日期:2016-12-10 00:00:00
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970630)16:12<1391::aid-s
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journal_title:Statistics in medicine
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