Abstract:
:Estimating the causal effect of quitting smoking on time to death or first myocardial infarction requires that one control for the differences in risk factors between individuals who elect to quite at each time t versus those who elect to continue smoking at time t. In this paper we examine the limitations of standard time varying Cox proportional hazards models to yield tests and estimates of this effect. Implementing the method of G-estimation proposed by Robins, we perform an observational analysis of data from the Multiple Risk Factor Intervention Trial (MRFIT) and estimate the causal effect of cigarette cessation while controlling for such time varying confounders as angina. We reject the null hypothesis of no effect of quitting on time to failure, and estimate that by quitting smoking, an individual increases by 50 per cent his time to death or first myocardial infarction (MI).
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Mark SD,Robins JMdoi
10.1002/sim.4780121707subject
Has Abstractpub_date
1993-09-15 00:00:00pages
1605-28issue
17eissn
0277-6715issn
1097-0258journal_volume
12pub_type
杂志文章,多中心研究abstract::The induced smoothing technique overcomes the difficulties caused by the non-smoothness in rank-based estimating functions for accelerated failure time models, but it is only natural when the estimating function has Gehan's weight. For a general weight, the induced smoothing method does not provide smooth estimating f...
journal_title:Statistics in medicine
pub_type: 杂志文章
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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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更新日期:1993-09-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:2003-02-28 00:00:00
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章
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pub_type: 杂志文章,评审
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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
doi:10.1002/1097-0258(20010215)20:3<401::aid-sim801>3.
更新日期:2001-02-15 00:00:00
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journal_title:Statistics in medicine
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pub_type: 杂志文章
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journal_title:Statistics in medicine
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