What you presented below is not an odds ratio, but simply the odds of disease when some measure is less than 40%. But you can use the oddsratio() function from the epitools package to do the calculations that you want.
Hope this is helpful, Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 From: C W [mailto:tmrs...@gmail.com] Sent: Tuesday, August 14, 2012 11:59 AM To: Nordlund, Dan (DSHS/RDA) Cc: r-help Subject: Re: [R] What package to use to calculate odds ratio and the confidence interval? Suppose my results comes out like this, <40% >40% Total No disease 131 75 206 Have disease 27 6 33 239 My odds ratio: 27/(27+131))/(131/(27+131)) = 0.206 I want to calculate the confidence interval for it. Mike On Tue, Aug 14, 2012 at 2:52 PM, Nordlund, Dan (DSHS/RDA) <nord...@dshs.wa.gov<mailto:nord...@dshs.wa.gov>> wrote: > -----Original Message----- > From: r-help-boun...@r-project.org<mailto:r-help-boun...@r-project.org> > [mailto:r-help-bounces@r-<mailto:r-help-bounces@r-> > project.org<http://project.org>] On Behalf Of C W > Sent: Tuesday, August 14, 2012 11:18 AM > To: r-help > Subject: [R] What package to use to calculate odds ratio and the > confidence interval? > > Hi list, > I am trying to calculate the sensitivity, specificity, and odds > ratio(and > confidence interval). > Say, my data looks like this > > 42.53, 37.56, 40.51, 32.67, 38.19, 81.74, 41.55, 68.94, 59, 63, 54.13, > 48.85, 50.46, 51.78 > > Is there any packages in R that does this? Espeically the odds ratio > confidence interval. > > Mike You need to provide more information than you have. The odds of something happening is the probability of it happening divided by (1-probability). To calculate the odds ratio, you need to have odds for two different groups. I suspect you need to get some local statistical assistance on these concepts before you will get much help on R packages and functions. Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 ______________________________________________ R-help@r-project.org<mailto:R-help@r-project.org> mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
