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rplotstatisticslabelaxes

using the addpoly function in a forest plot - metafor package

I would like to add a polygon to a forest plot with the following label:

"I2 = 92.2%"

wherein the "2" is superscripted and "92.2%" is recalled from an rma object (i.e. res$I2).

Here is a made-up example: 

library(metafor)
data(dat.bcg)
res <- rma(ai=tpos, bi=tneg, ci=cpos, di=cneg, data=dat.bcg, measure="RR", 
           method="REML")
forest(res)
addpoly(res,mlab=*)

What should * be?

The below does not superscript "2":

paste("I2 = ",round(res$I2,1),"%"))

The below does not work at all.

bquote(I^2==.(round(res$I2,1))*"%")
Solution

  • You have to turn the result from bquote() into an expression:

    addpoly(res, mlab=as.expression(bquote(I^2==.(round(res$I2,1))*"%")))