Well, except that you didn't address a single fucking thing I said with that worthless reply. Other than to (unintentionally) comfirm everything I said.
1.) No, there were no control groups, and there was no actual study.
2.) Instead, it was basically just a worthless fucking questionaire with zero research into whether or not the answers were correct, honest, or accurate (and yes, all three of those things are different).
3.) They had no way of knowing what was or wasn't a "physical disciplinary action that were considered abusive" except people's word on the subject.
4.) There seems to be no indication that they looked into other causes of why people allegedly turned out for the worse.
5.) It is indeed a worthless piece of shit "study" because of all three of those reasons. It might as well have been a fucking poll on a message forum asking "does drinking Kool-Aid make you a homicidal maniac? Because 80% of all homicidial maniacs have tasted Kool-Aid before; ergo, Kool-Aid makes you a homicidial maniac. Do you agree or not?"