I'm just facing an issue of finding an easy tutorial or guide to the funnel plot
.
Are there simple resources you recommend for this?
Thanks.
Do you mean interpreting this? Here are a couple of other descriptions:
2."Funnel plots in Meta Analysis" by Sterne & Harbord
3."Funnel plots for detecting bias in meta-analysis: guidelines on choice of axis" by Sterne & Egger
But the wikipedia link is probably the best place to start. (It also contains a few other refs).