[R-meta] Overlapping CIs with significant difference among subgroups

Dear Rafael,

CIs can overlap and yet the difference between the two levels can be
significant. See, for example:


https://towardsdatascience.com/why-overlapping-confidence-intervals-mean-nothing-about-statistical-significance-48360559900a?gi=b673a691634d


https://www.psychologicalscience.org/observer/understanding-confidence-intervals-cis-and-effect-size-estimation


https://blog.minitab.com/blog/real-world-quality-improvement/common-statistical-mistakes-you-should-avoid

and many more (just google for "test difference overlapping confidence
intervals" or something along those lines). They don't talk about
meta-analysis per se, but it's the same principle.

So, you can trust the test of the difference between the levels of the
moderators.

Best,
Wolfgang

-----Original Message-----
From: Rafael Rios [mailto:biorafaelrm at gmail.com]
Sent: Monday, 01 June, 2020 21:54
To: r-sig-meta-analysis at r-project.org; Viechtbauer, Wolfgang (SP)
Subject: Overlapping CIs with significant difference among subgroups

ATTACHMENT(S) REMOVED: dataset.csv | pruned_super-tree.tre | script.R

Dear Wolfgang and All,

I conducted a multilevel mixed-effects meta-analysis and found differences
between levels of two moderators. I was expecting to find non-overlapped
confidence intervals. However, I obtained overlapped confidence intervals
for all subgroups. How can I interpret these results? In such situation,
should I trust in the Q-test or in the CIs? I controlled for phylogenetic
non-independence. Is there a chance of this approach affect the estimation
of CIs using predict function? My dataset and script are attached.

Best wishes,