Abstract:
:Prevention studies, as distinguished from studies investigating treatments for established disease, present some distinct challenges. Perhaps the most extensive experience with preventive agents is in the area of infectious diseases; vaccines have been extremely effective in preventing many such diseases. Vaccines have been, and continue to be, studied in other disease areas such as certain cancers, but as yet have not achieved success outside of infectious disease prevention. One obvious and important feature of prevention studies is that they enroll healthy individuals; thus such studies require particularly high standards for the safety of those enrolled (and those who might ultimately receive the product being tested). Prevention studies often need to be quite large, as the types of diseases most important to prevent tend to be uncommon. Large studies usually require simplified approaches; to ensure high quality of data on the key variables it may be necessary to compromise on the amount of data collected, frequency of data collection, and other aspects of trial design. The reliability of randomization and blinding may be especially important in these large studies, as bias could easily overwhelm the small effects that are usually sought. Often, biomarkers thought to indicate developing but as yet subclinical disease, will be important to evaluate; whether such markers can serve as primary endpoints in prevention studies has been a contentious issue in many contexts. Studies in older populations, such as those at risk for Alzheimer's Disease, raise challenges such as accounting for competing risks, and considering potential interactions of preventive agents with multiple medications often used by the elderly.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Ellenberg SSdoi
10.1002/sim.1717subject
Has Abstractpub_date
2004-01-30 00:00:00pages
297-303issue
2eissn
0277-6715issn
1097-0258journal_volume
23pub_type
杂志文章abstract::In recent years randomized trials designed to establish non-inferiority of a new treatment as compared to a standard one have been more widely used. Two-sample statistics have been proposed for this equivalence testing problem. However, they are not suited to situations where a long-term survivor fraction is expected....
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journal_title:Statistics in medicine
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journal_title:Statistics in medicine
pub_type: 杂志文章,评审
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pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:2009-02-15 00:00:00
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pub_type: 杂志文章
doi:10.1002/sim.4255
更新日期:2011-07-30 00:00:00
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doi:10.1002/sim.2424
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780101209
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doi:10.1002/sim.4780110802
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journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1097-0258(19980815/30)17:15/16<1829:
更新日期:1998-08-15 00:00:00
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pub_type: 杂志文章
doi:10.1002/sim.4780110804
更新日期:1992-06-15 00:00:00
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更新日期:2012-11-20 00:00:00
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pub_type: 临床试验,杂志文章,随机对照试验
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