Recent content by gopher

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    Parallel Bioequivalence Study Sample Size

    I need to calculate the required sample size given the following information: Power=80% Coefficient of variation for Cmax and AUC = 40% True ratio of the geometric means=0.95(1.05) Probability that the 90% CI of the ratio falls into the range 0.80 to 1.25 is 80% In addition, we...
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    comparing change from baseline (two treatment groups, binomial data)

    I am comparing the effectiveness of a vaccine in reducing the prevalence of the targeted protein. I have baseline data (before the vaccine was even available), and now have data from vaccinated and non-vaccinated individuals. I have used chi-square/odds-ratios to show that the prevalence of...
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    Sample Size calculations with sub-groups

    I am in a situation wher we need to recruit 1600 people with a particular condition (calculated so that we can detect a 5% change following intervention). We also want to test the intervention on a particular sub-type (drug-users), where we expect a higher prevalence of the condition, and want...