Exact group sequential designs for two-arm experiments with Poisson distributed outcome variables.
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ABSTRACT:
SUBMITTER: Grayling MJ
PROVIDER: S-EPMC7116540 | biostudies-literature | 2021
REPOSITORIES: biostudies-literature
Publications
Exact group sequential designs for two-arm experiments with Poisson distributed outcome variables.
Grayling Michael J MJ Wason James M S JMS Mander Adrian P AP
Communications in statistics: theory and methods 20190617 1
We describe and compare two methods for the group sequential design of two-arm experiments with Poisson distributed data, which are based on a normal approximation and exact calculations respectively. A framework to determine near-optimal stopping boundaries is also presented. Using this framework, for a considered example, we demonstrate that a group sequential design could reduce the expected sample size under the null hypothesis by as much as 44% compared to a fixed sample approach. We conclu ...[more]
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