On 13 Mar 2003 at 10:45, Cook Jane wrote:
> I've just joined up with a project that's already been going, and am trying to duplicate a sample size calculation. The original proportion of the population with a characteristic is 50%, and we want to detect a 10% increase with 80% power at the 5% level of significance. I'm told we'd need
407 patients, but can't get this number myself. Could someone point me to a formula or reference for sample size calculations.
Try my calculator, downloadable from http:\www.difftest.co.uk
Sandy MacRae
StatBasics
6, Ascot Road
Moseley
Birmingham
B13 9EL
Phone / Fax: 0121 247 6138
http://www.statbasics.co.uk
http://www.difftest.co.uk
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