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PubMed · 4023473

Power, sample size and smallest detectable effect determination for multivariate studies.

S Greenland
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Abstract

This paper discusses some general methods for determining approximate power, sample size, and smallest detectable effect for studies of multiple risk factors. These methods are based on standard large-sample formulae for determining the power of chi-square tests, and emphasis is given to determinations for Pearson chi 2 tests in multiway contingency tables. The methods are illustrated in application to the design of a clinical trial of the preventive effect of alpha-tocopherol, ascorbic acid and beta-carotene on colon polyp recurrence, and a case-control study of the joint effect of smoking and asbestos exposure on lung cancer incidence.

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BiometryClinical Trials as TopicColonic PolypsEpidemiologic MethodsHumansLung NeoplasmsRecurrenceJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S Greenland. Power, sample size and smallest detectable effect determination for multivariate studies.. https://doi.org/10.1002/sim.4780040203

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