This is not what we would call a paired design, because you are not pairing the OUTCOME, but the EXPOSURE.
You are merely taking a sample of the exposed and a sample of the non-exposed, and making sure that they have the same distribution of age at entry / date of birth / date of entry --- which one(s)? Estimating mortality (morbidity?) in each of the two groups and the rate-ratio between them is just a straight-forward cohort analysis, either using a Poisson-model or a Cox-model. You will have to consider what time-scale you use for the description, though. And you must be sure that you are not using any of the follow-up information in your selection of persons to enter the study. Best regards, Bendix Carstensen ______________________________________________ Bendix Carstensen Senior Statistician Steno Diabetes Center Niels Steensens Vej 2-4 DK-2820 Gentofte Denmark +45 44 43 87 38 (direct) +45 30 75 87 38 (mobile) [EMAIL PROTECTED] http://www.biostat.ku.dk/~bxc > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > Pedro Emmanuel Alvarenga Americano do Brasil > Sent: 5. september 2008 16:01 > To: r-sig-epi@stat.math.ethz.ch > Subject: Re: [R-sig-Epi] Paired by exposure > > > > > Dear R friens, > > > > I will start a project this month wiht a partner which is > disigned as > > a quasi-experiment. We are interrested in estimate risk > raios and rate > > ratios, possibly survival analysis. Everything is registered at > > medical charts form the last 22 yaers. So everythig is > retorspective. > > However, due to a efficiency matters, we dicided to select the > > non-exposed matching to the exposed. So for every paciente > that took > > this paticular medicine, we intend ot match one that did > not take, and > > start the follow-up in the same year and has no more than > 10 years older than the exposed. > > > > I have looked up for more recent things than those I have > in Klienbaum > > and Rothman but it seems that the very good old friend > ajusted MH for > > the pair is the recomended. > > > > Does anyone have other sugestions? Does any knows a package or > > functions to run paired risk or rate analysis? > > > > Best regards > > > > > -- > > Abraço forte e que a força esteja com você, Pedro Emmanuel > > > > [[alternative HTML version deleted]] > > _______________________________________________ R-sig-Epi@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-sig-epi
