Somewhat offtopic:

I recall reading a study once that used a test which I am almost certain was this one to try to answer the cause/correlation question of whether philosophical training/credentials improved one's critical thinking or whether those who undertook philosophy already had good critical thinking skills; when I recently tried to re-find it for some point or other, I was unable to. If anyone also remembers this study, I'd appreciate any pointers.

(About all I can remember about it was that it concluded, after using Bayesian networks, that training probably caused the improvements and didn't just correlate.)