Abstract:
:Dunnett's many-to-one test is used frequently today, especially in dose-finding studies. Using Dunnett's test, the Type I error level for the comparison between the raw mean of the control and the raw means of the study drug groups can be exactly calculated for the normal data. However, this computability depends on the independence of the raw means. Unfortunately, this independence does not exist for the model-based likelihood estimates (least square means) in the cases of ANCOVA and two-way ANOVA models without interaction for unbalanced data. This paper investigates this dependence between the least square means and derives some new procedures to calculate the joint distribution of the statistic for Dunnett's test.
journal_name
J Biopharm Statjournal_title
Journal of biopharmaceutical statisticsauthors
Shun Z,Silverberg A,Chang CK,Ouyang Pdoi
10.1081/BIP-120017723keywords:
subject
Has Abstractpub_date
2003-02-01 00:00:00pages
17-28issue
1eissn
1054-3406issn
1520-5711journal_volume
13pub_type
杂志文章abstract::In clinical trials of drug development, patients are often followed for a certain period of time, and the outcome variables are measured at scheduled time intervals. The main interest of the trial is the treatment efficacy at a prespecified time point, which is often the last visit. In such trials, patient dropout is ...
journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章,评审
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2017.1372766
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abstract::It has been widely recognized that interim analyses of accumulating data in a clinical trial can inflate type I error. Different methods, from group sequential boundaries to flexible alpha spending functions, have been developed to control the overall type I error at prespecified level. These methods mainly apply to t...
journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2014.919936
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abstract::The potency of a batch of drug product needs to meet a release limits at the time of release so that the potency at the end of shelf life remains above the lower registration limit (LRL). This article discusses two methods which determine the release limits such that the chance to fail LRL at the end of shelf life of ...
journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543409808835225
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2014.972515
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543409608835129
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2015.1052495
更新日期:2016-01-01 00:00:00
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2014.941991
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
doi:10.1080/10543406.2014.920343
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journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
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更新日期:1999-05-01 00:00:00
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章
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journal_title:Journal of biopharmaceutical statistics
pub_type: 杂志文章,评审
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journal_title:Journal of biopharmaceutical statistics
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journal_title:Journal of biopharmaceutical statistics
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