• J Clin Epidemiol · Jul 2004

    Null bar and null zone are better than the error bar to compare group means in graphs.

    • Maarten Boers.
    • Department of Clinical Epidemiology and Biostatistics, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. keb.info@vumc.nl
    • J Clin Epidemiol. 2004 Jul 1; 57 (7): 712-5.

    The ProblemConventional graphs often include error bars around the group means. Regardless of what these bars depict, they are uninformative as to whether a difference between the groups is statistically significant.The SolutionThis article suggests plotting the null bar or null zone: that is, the range or area in which the means of the two groups fall if the null hypothesis of no difference cannot be rejected. The bar and zone are simply derived from the confidence interval around the difference, obtained from the t-test.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…