Abstract:
:In some randomized controlled trials, subjects with a better prognosis may be diverted into the treatment group. This subverting of randomization results in an unobserved non-compliance with the originally intended treatment assignment. Consequently, the estimate of treatment effect from these trials may be biased. This paper clarifies the determinants of the magnitude of the bias and gives a sensitivity analysis that associates the amount that randomization is subverted and the resulting bias in treatment effect estimation. The methods are illustrated with a randomized controlled trial that evaluates the efficacy of a culturally sensitive AIDS education video.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Marcus SMdoi
10.1002/sim.715subject
Has Abstractpub_date
2001-02-28 00:00:00pages
545-55issue
4eissn
0277-6715issn
1097-0258journal_volume
20pub_type
杂志文章abstract::In the field of cluster detection, a weighted normal model-based scan statistic was recently developed to analyze regional continuous data and to evaluate the clustering pattern of pre-defined cells (such as state, county, tract, school, hospital) that include many individuals. The continuous measures of interest are,...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3990
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8099
更新日期:2019-05-30 00:00:00
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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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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/(sici)1097-0258(19980315/15)17:5/7<613::ai
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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.4780100802
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100308
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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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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.2751
更新日期:2007-06-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
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pub_type: 杂志文章
doi:10.1002/sim.7522
更新日期:2018-02-10 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780131708
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8378
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7606
更新日期:2018-05-10 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8799
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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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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.2776
更新日期:2007-09-10 00:00:00
abstract::A statistical definition of surrogate endpoints as well as validation criteria was first presented by Prentice. Freedman et al. supplemented these criteria with the so-called proportion explained. Buyse and Molenberghs pointed to inadequacies of these criteria and suggested a new definition of surrogacy based on (i) t...
journal_title:Statistics in medicine
pub_type: 评论,杂志文章
doi:10.1002/sim.923
更新日期:2001-10-30 00:00:00
abstract::Data monitoring committees (DMCs) have become an increasingly common component of randomized clinical trials in recent years. As experience has accumulated, and more individuals and organizations have become involved in such activities, a variety of approaches to the operation of such committees has inevitably arisen....
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.730
更新日期:2001-09-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780060304
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8485
更新日期:2020-05-15 00:00:00
abstract::Results from an analysis of traffic accidents from a study of the police records of four police stations in the Bangkok metropolis are presented. The main emphasis in this study was put on the development of a measure for traffic accident density. The traffic flow was estimated at the various study locations by traine...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780142113
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