Carlo wrote:
I would like to compare three incidence rates (the only effectiveness end
point available) concerning three group of patients with the same disease,
treated with three different drugs and followed-up for six months.
Is there any way to do it in Stata/SE 9.2? Is there any reference about your
hints?
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Carlo,
It is not quite clear to me what you mean by "compare three incidence
rates". Is it a question of significant difference or estimation of
incidence rate ratios or rate differences? And do you want to compare
B vs A and C vs A only, or do you also want to compare B vs C?
Below I used -ci- to estimate the individual incidence rates and
-poisson- to estimate incidence rate ratios (imagine that -agecat-
represents the drugs to be compared).
webuse dollhill3.dta
by agecat, sort: ci deaths, poisson exposure(pyears)
xi: poisson deaths i.agecat, exposure(pyears) irr
Hope this helps
Svend
________________________________________________________
Svend Juul
Institut for Folkesundhed, Afdeling for Epidemiologi
(Institute of Public Health, Department of Epidemiology)
Vennelyst Boulevard 6
DK-8000 Aarhus C, Denmark
Phone, work: +45 8942 6090
Phone, home: +45 8693 7796
Fax: +45 8613 1580
E-mail: [email protected]
_________________________________________________________
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