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How many patients do we need for a clinical trial? Demystifying sample size calculations
Patrick J Kelly1, Angela C Webster, Jonathan C Craig
1University of Sydney, Sydney, Australia. p.kelly@sydney.edu.au
Abstract:
Determining the number of subjects required for a study is a critical component when planning a research project. An adequate number of patients are needed in order to be able to answer the research question of interest with a degree of certainty. In this paper, the information that is required for determining the sample size is described. The primary aim is to demystify the sample size section in published clinical trials. Some of the difficulties in determining the sample size correctly are also highlighted and some good practices recommended.
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