1. K

    Calculating sample size for non-inferiority trial using Stata cii

    Hi, can I use Stata command cii to calculate the sample size required if I want to test that fasting TG is not lower than non-fasting TG by 0.2mmol/l? Given mean=1.4, sd=0.5, 95% confidence level. What is the exact command? How do I calculate sample size if I want to test for equivalence of...
  2. klapacius

    Wich margin of non-inferiority to pick?

    Hi everyone, I have been thinking about this quite long: Event rate of death in particular sick population is 22% Treatment A has a relative risk to placebo at 0,4 (95% CI 0,18-0,9) If I want to perform a non-inferiority trial what margin of non-inferiority should I use?
  3. T

    Fisher's exact test and non-inferiority / equivalence

    I have some data (multiple choice question scores for two groups of medical students exposed to an experimental and standard type of anatomy teaching). It's ordinal data (scores out of 10). I'd like to test whether the experimental type of teaching is equivalent (i.e. not inferior) to the...
  4. A

    Determining an indirect confidence interval for justifying a non-inferiority margin

    I need to establish the efficacy of a test treatment (T) by means of an indirect comparison to placebo (P). Therefore a study of T vs. reference (R) will be performed, and there is 'historical' data for the comparison between R and P. The outcome measure of interest is a responder rate (i.e...