-
- S Todd and M Sahdra.
- Medical & Pharmaceutical Statistics Research Unit, The University of Reading, Berkshire, UK. s.c.todd@reading.ac.uk
- J Biopharm Stat. 2001 Nov 1; 11 (4): 297-311.
AbstractRecent literature has discussed the value of adjustment for important covariates in models involving nonnormal data. It is generally concluded that, when performing traditional "fixed sample size" clinical trials, covariate adjustment influences the magnitude of the treatment effect but has little effect on precision of the estimate. In fact, it may actually reduce it. In this paper, we investigate the effect of covariate adjustment in the sequential setting via a case study of a survival clinical trial. Sequential and fixed sample analyses are compared, with and without covariate adjustment of the treatment effect. It was found that conclusions similar to those for the fixed sample size case also apply in the sequential case, but that incorporation of covariate information can present added complications in this setting.
Notes
Knowledge, pearl, summary or comment to share?You can also include formatting, links, images and footnotes in your notes
- Simple formatting can be added to notes, such as
*italics*
,_underline_
or**bold**
. - Superscript can be denoted by
<sup>text</sup>
and subscript<sub>text</sub>
. - Numbered or bulleted lists can be created using either numbered lines
1. 2. 3.
, hyphens-
or asterisks*
. - Links can be included with:
[my link to pubmed](http://pubmed.com)
- Images can be included with:

- For footnotes use
[^1](This is a footnote.)
inline. - Or use an inline reference
[^1]
to refer to a longer footnote elseweher in the document[^1]: This is a long footnote.
.