you also have “operative definitions” which taint the sample.
ie when the libs wanted to make all video games cause violence. They defined a violent act as “pressing a button” regardless of the effect caused. (reset, jump, pause etc)
So now the psychologists just define violent as having “conservative thoughts” and presto no sane person is conservative.
I still like the old study that found 45% of doing ANYTHING would have the same result as psychological treatment. (or that no training was required to interprit ink blot studies)
All “normal” teenagers have homosexual feelings.
Our whole society is stewing in that manipulative garbage.