The Importance of Causality in Research

The other thing that occurs to me you could do with this identification strategy is do more on the efficacy of the flu vaccine. So there's a fair amount of variation in efficacy across years, right? Sometimes the flu is 10%, sometimes it's 30% or 40%. You could use that, right? I mean, you're linking now shots to flu, you could back out efficacy based on the effect size over time. That was a very clever idea. And also, I also the cardiologist, but I actually want to pivot and talk a little bit about these issues of causality and, and why the medical literature is not good at this often.