This is Altman's nomogram with an line added joining 0.625 on teh left Standardised difference axis to 0.90 on the right Power axis. It intersectsthe upper sloping line for significance level 0.05 at N = 108 and the lower sloping line for significance level 0.01 at about N = 150.
Read description of Altman's nomogram.
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This page maintained by Martin Bland.
Last updated: 15 July, 2009.