Sample size and power calculations for trials and quasi-experimental studies with clustering
Evridiki Batistatou
Institute of Population Health
Centre for Epidemiology
University of Manchester
Manchester, UK
[email protected]
|
Chris Roberts
Institute of Population Health
Centre for Biostatistics
University of Manchester
Manchester, UK
[email protected]
|
Steve Roberts
Institute of Population Health
Centre for Biostatistics
University of Manchester
Manchester, UK
[email protected]
|
Abstract. This article considers the estimation of power and sample size in experimental
and quasi-experimental intervention studies, where there is clustering of
subjects within one or both intervention arms, for both continuous and binary outcomes.
A new command, clsampsi, which has a wide range of options, calculates
the power and sample size needed (that is, the number of clusters and cluster size)
by using the noncentral F distribution as described by Moser, Stevens, and Watts
(1989, Communications in Statistics—Theory and Methods 18: 3963–3975). For
comparative purposes, this command can also produce power and sample-size estimates
on the basis of existing methods that use a normal approximation.
View all articles by these authors:
Evridiki Batistatou, Chris Roberts, Steve Roberts
View all articles with these keywords:
clsampsi, sample size, power calculation, intervention studies
Download citation: BibTeX RIS
Download citation and abstract: BibTeX RIS
|
