Dangerous Goods your posts are really not much use. You ask for empirical evidence which has been posted already above.
You still do not comprehend what I have been trying to tell you. You are obviously a hopeless case. Hence it is pointless having a conversation with you about the scientific method.
For your information there have been PRCTs of all sorts of interventions, and surgery is no exception. There have been trials with dummy incisions etc - there was a study published last year I think that proved that arthroscopic lavage was no better than simply following the perioperative regimen.
Still you persist with your erroneous understanding of what a control is for, forgetting that Gallstones and faeces have been analysed many times before.
Believe what you want, since obviously nothing will persuade you.