Abstract:
:Patient reported outcome and observer evaluative studies in clinical trials and post-hoc analyses often use instruments that measure responses on ordinal-rating or Likert scales. We propose a flexible distributional approach by modeling the change scores from the baseline to the end of the study using independent beta distributions. The two shape parameters of the fitted beta distributions are estimated by matching-moments. Covariates and the interaction terms are included in multivariate beta-regression analyses under generalized linear mixed models. These methods are illustrated on the treatment satisfaction data in an overactive bladder drug study with four treatment arms. Monte-Carlo simulations were conducted to compare the Type 1 errors and statistical powers using a beta likelihood ratio test of the proposed method against its fully nonparametric or parametric alternatives.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Zou KH,Carlsson MO,Quinn SAdoi
10.1002/sim.4012subject
Has Abstractpub_date
2010-10-30 00:00:00pages
2486-500issue
24eissn
0277-6715issn
1097-0258journal_volume
29pub_type
杂志文章abstract::Sam Greenhouse joined the Census Bureau as a clerk at an interesting time period for the agency. The first use of sampling in the decennial census occurred in 1940. There was a major expansion of the amount of data collected. The organization of the Census Bureau underwent radical changes, including the growth of the ...
journal_title:Statistics in medicine
pub_type: 传,历史文章,杂志文章
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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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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
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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:2017-06-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2653
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更新日期:2017-01-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780131007
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8813
更新日期:2021-02-20 00:00:00
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pub_type: 杂志文章
doi:10.1002/sim.6478
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