Abstract:
:Patients who switch treatment groups in randomized clinical trials can cause problems in the interpretation of the results. Although the intention-to-treat method is recognized as being the most reliable analysis, it may result in an underestimate of the treatment effect if there have been patients who switch treatments. In this paper, an adjusted analysis, based on a Cox model, is proposed which estimates the treatment effect allowing for patients who switch treatments. Because this analysis requires much weaker assumptions than 'as treated' analyses, it is likely to be much more reliable. The method is illustrated by a trial comparing radical radiotherapy with radiotherapy followed by cystectomy in the treatment of invasive bladder cancer.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Law MG,Kaldor JMdoi
10.1002/(SICI)1097-0258(19961015)15:19<2069::AID-Ssubject
Has Abstractpub_date
1996-10-15 00:00:00pages
2069-76issue
19eissn
0277-6715issn
1097-0258pii
10.1002/(SICI)1097-0258(19961015)15:19<2069::AID-Sjournal_volume
15pub_type
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pub_type: 杂志文章
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pub_type: 临床试验,杂志文章,随机对照试验
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pub_type: 杂志文章
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更新日期:1995-08-30 00:00:00
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更新日期:2000-05-30 00:00:00
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