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PubMed · 9483715

Estimating sample size for continuous outcomes, comparing more than two parallel groups with unequal sizes.

J Singer
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Abstract

This paper contains a short generalization of a known method for sample size determination in the case of more than two parallel groups. The term 'set of allocation ratios' corresponding to the allocation ratio from the two-group design is defined. A formula using these ratios to determine the non-centrality parameter of the F distribution is deduced. It is shown that in case of more than two groups, equal group numbers does not constitute an optimal design. Two worked examples are presented.

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BibTeXRIS

J Singer. 1997-12-30. Estimating sample size for continuous outcomes, comparing more than two parallel groups with unequal sizes.. https://doi.org/10.1002/(sici)1097-0258(19971230)16%3A24%3C2805%3A%3Aaid-sim676%3E3.0.co%3B2-b

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