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Thread: Appropriate Bonferroni correction

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    Appropriate Bonferroni correction




    I'm comparing two groups of patients using several 3x2 and 4x2 contingency tables (for different sublevels of chemotherapy for instance). Question is how much do I need to adjust P value using Bonferroni correction (for 4 or 6 comparisons when analyzing 2x4 table, for 5 or 10 comparisons when analyzing 5x2 table). In this example I intend to find out do two groups differ in specific chemotherapies, Chemo 1 and Chemo 4 significantly differ, but what about Chemo 2?

    Table looks like this:

    Overall P <0.001

    Variable / Group1 / Group2 / P value
    Chemo 1 / 60 / 0 / <0.001
    Chemo 2 / 40 / 1 / 0.011
    Chemo 3 / 6 / 2 / 0.172
    Chemo 4 / 1 / 8 / <0.001

  2. #2
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    Re: Appropriate Bonferroni correction


    the conservative approach is correcting for each possible comparison. For example:


    1 vs 2
    1 vs 3
    1 vs 4
    2 vs 3
    2 vs 4
    3 vs 4


    So multiply pvalues by 6.
    Stop cowardice, ban guns!

  3. The Following User Says Thank You to hlsmith For This Useful Post:

    Markica85 (10-19-2017)

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