When using meta-regression with factor moderators, result differ a bit from using seperate estimation based on subgroup, even if the same model (mixed effects) is used for both. I understand the difference mostly stems from estimation of $\tau^2$. I can't say from data, but it seem the subgroup-based method is more usually used for forest plots.
I'm using R and metafor, and it's easy to add subgroup polygons, but not with results from meta-regression. Am I wrong in assuming this is for a reason? Wouldn't it be better to display results from meta-regresson, unlessof course differences in amount of heterogeneity are of interest?