As a statistical aside, I see no strong reason to believe a meta-analysis should be any more convincing than a single, large, well-designed study. In fact, by mixing the results of rigorous studies in with the unrigorous ones, you’re probably just diluting the signal to noise ratio.
We should feel good about the fact that some biases of different research designs will cancel each other out, while bad about our inability to weight each study optimally.
As a statistical aside, I see no strong reason to believe a meta-analysis should be any more convincing than a single, large, well-designed study. In fact, by mixing the results of rigorous studies in with the unrigorous ones, you’re probably just diluting the signal to noise ratio.
We should feel good about the fact that some biases of different research designs will cancel each other out, while bad about our inability to weight each study optimally.
Does anyone claim it is? I thought the advantage of a meta-analysis was the cost savings of not having to do a new, large study.