Discussions praising the efficiency of randomized trials are widespread, however, few of these discussions take a close look at some of the common assumptions that individuals hold regarding randomized trials. And unfortunately, these common assumptions may be based on outdated evidence and simplistic ideas.
Meta-analyses are widely used to summarize and examine treatment effects. However, few researchers examine the relationship between power and meta-analyses. In this post, I discuss power conceptually and mathematically. Then I explain how different models impact power and the problems with under-powered meta-analyses.