Journal
CONTEMPORARY CLINICAL TRIALS
Volume 28, Issue 4, Pages 451-458Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.cct.2006.11.003
Keywords
center effect; intraclass correlation coefficient; multicenter randomized trial; sample size
Ask authors/readers for more resources
In multicenter trials, data from the same center are more similar than those from different centers. These similarities induce a correlation between data, known as the center effect, which is assessed by the intraclass correlation coefficient (ICC). Here, we derive a sample size formula for continuous data that takes into account this center effect. Our analytical developments lead to an elementary formula different from the classical one by a (1-rho) factor, where rho is the ICC. This work allows for adjusting and reducing the sample size according to the magnitude of the center effect and leads to a better consistency in the conduct of multicenter randomized trials. (c) 2006 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available