There are meta-analysis×654 and meta-regression×101 tags. Meta-regression is a particular approach to meta-analysis so it's a subset tag. 90 out of 101 Qs are also tagged with [meta-analysis], i.e. there are almost no questions tagged with [meta-regression] only. Given that, do we really need this tag, or should it perhaps be merged into [meta-analysis] (which will only increase the question count there by 11)?
On a related note, I have recently learned that there are fixed effects models, random effects models, and mixed effects models in meta-analysis (see brief but very clear Chapter 2 in https://www.jstatsoft.org/article/view/v036i03/v36i03.pdf). Obviously, people use our [random-effect-model], [fixed-effect-model], and [mixed-model] tags in combination with [meta-analysis], but in fact these models in meta analysis are clearly distinct from mixed models (e.g. you cannot fit them with
lmer). Confusing! So I suggest to create tags like
[meta-analysis-mixed-effects] as synonyms of [meta-analysis].
@mdewey wrote me elsewhere that
I do not see any pressing need for meta-analysis tagged questions to also have a random effects tag (or fixed effects for that matter)
which I think is in line with what I suggest (?).
Finally, as far as I could understand "meta-regression" is another name for "mixed effects model in meta-analysis". Which might be another reason to make it a synonym. If not, then alternatively
[meta-analysis-mixed-effects] could point to [meta-regression].