Jokel Meyer
2011-Jul-18 16:44 UTC
[R] Extract confidence intervals from rma object (metafor package)
Dear R-experts! I am working on some meta-analysis using the metafor package. I would like to extract values of the confidence intervals of the effect sizes of the single studies from an rma object. Those values are printed out when plotting a forest plot using the forest function on the rma object, however I was not able to locate them. Many thanks for your help! Jokel [[alternative HTML version deleted]]
Viechtbauer Wolfgang (STAT)
2011-Jul-18 17:40 UTC
[R] Extract confidence intervals from rma object (metafor package)
Dear Jokel, Right now, none of the functions return that information. But it's easy to calculate those CIs by hand (simply take yi +- 1.96 sqrt(vi) and apply, if needed, some appropriate transformation). For example: data(dat.bcg) dat <- escalc(measure="RR", ai=tpos, bi=tneg, ci=cpos, di=cneg, data=dat.bcg, append=TRUE) exp(dat$yi - 1.96*sqrt(dat$vi)) exp(dat$yi + 1.96*sqrt(dat$vi)) gives you approximate 95% CIs for the RRs. The forest functions essentially do nothing different. I hope this helps! Best, -- Wolfgang Viechtbauer Department of Psychiatry and Neuropsychology School for Mental Health and Neuroscience Maastricht University, P.O. Box 616 6200 MD Maastricht, The Netherlands Tel: +31 (43) 368-5248 Fax: +31 (43) 368-8689 Web: http://www.wvbauer.com ________________________________________ From: r-help-bounces at r-project.org [r-help-bounces at r-project.org] On Behalf Of Jokel Meyer [jokel.meyer at googlemail.com] Sent: Monday, July 18, 2011 6:44 PM To: r-help at r-project.org Subject: [R] Extract confidence intervals from rma object (metafor package) Dear R-experts! I am working on some meta-analysis using the metafor package. I would like to extract values of the confidence intervals of the effect sizes of the single studies from an rma object. Those values are printed out when plotting a forest plot using the forest function on the rma object, however I was not able to locate them. Many thanks for your help! Jokel [[alternative HTML version deleted]] ______________________________________________ R-help at 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.