Dear all,
We are running a clinical trial to determine the efficacy of antibiotics
to
treat conjunctivitis. During the trial several infectious agents (or
possibly infectious) have been found which lead us to question which of
these agents would be found in a "normal" eye.
Since then, several controls have been taken looking for the agents found
in the cases. The question now is how many of these "controls" are
required to determine which agents are usually found in "healthy"
individuals?
As I mentioned the focus of the project is on the clinical trial and the
control group will be used only for descriptive purposes - we are not
interested in hypothesis testing between cases and controls. There are
several medical papers discussing some of the agents found for
conjunctivitis (though not all of them) but in none of them there has
been a reason for the number of "controls" taken.
Any advice would be most welcomed.
Rafael Perera
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