Re: st: Confidence interval for incidence rate

[Roger Newson <roger.newson@kcl.ac.uk>]

At 22:57 28/07/03 +0100, Paul O'Brien wrote:
> I can find confidence intervals for incidence rate ratio and difference but
> not a simple incidence rate.
One possibility is to use the -noconst- option with -poisson- and to use a 
dummy variate of ones. If you type

gene byte baseline=1
poisson y baseline,robust noconst irr

then the parameter estimated (named -baseline-) should be a baseline 
incidence rate. And if you type

gene byte baseline=1
poisson y x baseline,robust noconst irr

then the parameter -baseline- will be a baseline incidence rate for zero 
-x-, and the parameter -x- will be an exponential rate of increase per unit 
of -x-.

I hope this helps.

Roger



--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
King's College London
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Tel: 020 7848 6648 International +44 20 7848 6648
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Email: roger.newson@kcl.ac.uk
Website: http://www.kcl-phs.org.uk/rogernewson

Opinions expressed are those of the author, not the institution.

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