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Endgames Statistical question

Sample sizes

BMJ 2008; 337 doi: (Published 01 October 2008) Cite this as: BMJ 2008;337:a199
  1. John Fletcher, clinical epidemiologist
  1. 1BMJ, London WC1H 9JR
  1. jfletcher{at}

    Which of the following will affect the sample size calculation for a clinical trial? (There may be more than one correct statement.)

    • a) Power

    • b) Significance level

    • c) Size of effect to detect

    • d) Variability of primary outcome


    a, b, c, d—That …

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