st: Sample size calculation for dose response

["Tun, Waimar" <WTun@PCDC.ORG>]

Hello.

Anyone know how to do sample size calculations for studies looking at dose response?
Essentially, we want to see if levels of a biomarker (call it X) changes when subjects are inseminated with varying levels of semen (10 units, 100 units, 1000 units). The biomarker X would be a continuous variable. So I want to see the correlation between biomarker X and these 3 levels of semen.

Any guidance would be helpful.
Thanks.

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