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--- Xin Wei <xinwei@STAT.PSU.EDU> wrote:
> Hi, i have a question:
>
> I have four studies, each studies contain control group and one drug
> dose
> as follows:
> study1: control drug(1mg)
> study2: control drug(2mg)
> study3: control drug(4mg)
> study4: control drug(5mg);
> now I want to set model to compare the treatment effect while taking
> the
> difference of study into account, how can I do that ?
>
> I think of: model y=treatment study. But it does not sound right to
> me
> becasue not all the treatment levels are in each study.
>
> any one can help:
> thanks
>
Xin,
According to what you have presented, study and drug dosage are
completely confounded. You would not be able to examine the effect
of dosage while "taking the difference of study into account".
How did you get such data? And what were you asked to do with
these data? What do you know about differences between studies?
Were the studies conducted at different times? Are there different
protocols for how subjects were recruited or how the treatment was
administered? What exactly characterizes each study apart from
different drug dosage in the treatment group?
Dale
---------------------------------------
Dale McLerran
Fred Hutchinson Cancer Research Center
mailto: dmclerra@NO_SPAMfhcrc.org
Ph: (206) 667-2926
Fax: (206) 667-5977
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