If they wanted to do something useful they would access demographic records of mental institutions, for reliable and impartial data.
Discussion
do you think this would yield different results? I mean maybe you could argue that conservatives are just less likely to admit having been diagnosed or even going to a doctor but just by observing people in public life, most that I'd categorize as mentally unstable would be liberals as well 🤔 but you can also argue about what even a mental inlless is etc.. so I guess nothing can be proven ever.. however I found hat stereotypes usually only propagate if there is some truth to it 😉