Below you can find some suggestions and tips on getting started with the metafor package and how to obtain help if you get stuck.
A good starting place for those interested in using the metafor package is the following paper:
Viechtbauer, W. (2010). Conducting meta-analyses in R with the metafor package. Journal of Statistical Software, 36(3), 1–48.
You can download the paper from: http://www.jstatsoft.org/v36/i03/. If the package is installed, you should also be able to open the paper with
The purpose of the article is to provide a general overview of the metafor package and its capabilities (as of version 1.4-0). Not all of the functions and options are described in the paper, but it should provide a useful introduction to the package.
The official reference manual (pdf) for the package can be found on CRAN. The manual describes all of the functions in the package together with their arguments and options. In R, you can also start browsing the documentation by typing
help(metafor) (after loading the package with
You can also browse the documentation online here.
A diagram showing the various functions in the metafor package (and how they related to each other) can be found here. If the package is installed, you should also be able to open this diagram directly from R with the command
vignette("diagram") if you have the devel version of the metafor package installed).
If you need help with using the package, please post your question to one of the R Project mailing lists (in most cases, R-help is the best choice, but R-sig-mixed-models may be another option if your question pertains specifically to aspects related to multilevel/multivariate meta-analytic models that can be fitted by an appropriate mixed-effects model). That way, you have a larger audience that may be able to provide answers and other users can benefit from the information and answers provided there.
Please include the package name (i.e., metafor) in your post to the mailing list. Also, make sure you first read and follow the posting guide. And before you sent off a post, you should first check the archives of the R-help and the R-sig-mixed-models mailing lists (your question may already have been answered in the past). You can search the archives with:
Stack Exchange is a network of question and answer websites on diverse topics in many different fields. Two of the websites may be of particular interest to users of the metafor package, as questions about the package have already been raised (and answered) there: Cross Validated is a website for people interested in statistics, machine learning, data analysis, data mining, and data visualization and Stack Overflow is a website for professional and enthusiast programmers. You can search these sites directly for questions that may be related to the metafor package:
Again, the advantage of posting your question on these websites is that you have a larger audience that may be able to provide assistance and the answers provided will be available to other users in the future.