[R] Forest Plot

[Viechtbauer Wolfgang (STAT)]

If you just want a forest plot, then the forest() function.

If you have the betas and corresponding variances, then you can create a forest plot with:

forest(betas, varbetas)

And yes, estimate +/- 1.96*sqrt(variance of estimate) would be an *approximate* 95% CI.

Best,

--
Wolfgang Viechtbauer                        http://www.wvbauer.com/
Department of Methodology and Statistics    Tel: +31 (0)43 388-2277
School for Public Health and Primary Care   Office Location:
Maastricht University, P.O. Box 616         Room B2.01 (second floor)
6200 MD Maastricht, The Netherlands         Debyeplein 1 (Randwyck)


----Original Message----
From: Xin Ge [mailto:xingemaillist at gmail.com]
Sent: Sunday, December 06, 2009 00:40
To: Viechtbauer Wolfgang (STAT)
Cc: r-help at r-project.org
Subject: Re: [R] Forest Plot

> Thanks for your reply. Which function I should explore in "metafor"
> package for this kind of plot.
>
> Also I have to do a forest plot for "regressions estimates" (betas)
> and corresponding "sqrt(var)". I hope in this case there is no
> difference between std. error and std. deviation? So, a 95%
> confidence interval would be [estimate +/- 1.96*sqrt(variance of
> estimate)]. Am I correct in saying this?
>
> Thanks again,
> Xin
>
>
> On Sat, Dec 5, 2009 at 6:21 PM, Viechtbauer Wolfgang (STAT)
> <Wolfgang.Viechtbauer at stat.unimaas.nl> wrote:
>
> The figure that you linked to was produced with the "metafor"
> package. It can also be used to produce a forest plot if you have
> means and corresponding standard errors of the means. The standard
> error of a mean is equal to SD / sqrt(n), so as long as you also know
> the sample sizes (n), you can convert those standard deviations to
> the standard errors.
>
> Best,
>
> --
> Wolfgang Viechtbauer                        http://www.wvbauer.com/
> Department of Methodology and Statistics    Tel: +31 (0)43 388-2277
> School for Public Health and Primary Care   Office Location:
> Maastricht University, P.O. Box 616         Room B2.01 (second floor)
> 6200 MD Maastricht, The Netherlands         Debyeplein 1 (Randwyck)
> ________________________________________
> From: r-help-bounces at r-project.org [r-help-bounces at r-project.org] On
> Behalf Of Xin Ge [xingemaillist at gmail.com]
> Sent: Sunday, December 06, 2009 12:11 AM
> To: r-help at r-project.org
> Subject: [R] Forest Plot
>
>
> Hi All,
>
> I want to produce a similar "Forest Plot" as it is on the following
> link, but my data would be having only two columns (one for
> "Estimate" and other for "Std. Dev"). Can anyone suggest some
> function() {Package} which can take such file as an input and give
> following forest plot:
>
> http://bm2.genes.nig.ac.jp/RGM2/R_current/library/metafor/man/images/big_plot.rma.uni_001.png
>
> Thanks,
> Xin