It's nice to have a meta-analysis. I would usually prefer the meta-analysis for an effect size estimate. But I also generally live by the saying "you never see

It's nice to have a meta-analysis. I would usually prefer the meta-analysis for an effect size estimate. But I also generally live by the saying "you never see a clear picture of Bigfoot". If a phenomenon of serious interest is to be considered proven, there should be at least one conclusive high-quality study alongside any meta-analyses. As with many supposed dilemmas, it's nice to have both.