I think can not compare. If you want to compare, you must have same sample. I mean the surgical at least have same technical and same time.

You must have the same situation for comparing

This would create too many confounding variables and would therefore lessen the rigidity of your research. If it was the same surgeon, the same technique and the same operation then yes, but not two totally different surgeons with different skills etc. Their exposure to different learning experiences alone would not make it a valid comparison as a master in one could be merely mediocre in the other.

What is a hypothesis? The results of two different interventions by these two surgeons are different or equivalent? I think that if a method that tests equality is used (for example TOST test), the bias will disappear.

Good question. No! This is my first and foremost answer to start with. Competency is an individual ergonomic faculty that comes inherently. Surgeons are very poor in basic medical sciences and their knowledge of anatomy is extremely wanting. Most surgeons learn by mimicking their trainer and become confused when encountered with an unusual situation or unexpected result what we call complication. Once a celebrated British surgeon cut urinary bladder during hernia surgery. His assistant was shocked and exclaimed, "You have cut bladder"! The chief was unperturbed and continued his surgery including repair of the cut bladder. The patient did well and sent home in good condition. The surgeon said to his assistant fellow, "A good surgeon is who can deal with his own complication, instead of calling someone else to do his dirty job". The test of competency takes years to build. Not by counting the number of cases operated but by circumstances encountered. That fateful occasion may either come in days, months or years or may never come if lucky but that never happens because any surgeon who has performed enough surgery is bound to come across such a situation in their lifetime or s/he has not done enough surgery. The number will fail.

Yes, in my opinion it is something that we regularly do, for instance in the case of plastic surgery let's take the problem of the capsular contracture after a breast implant procedure. Some surgeons putting the implant behind the muscle and published their statistics compare their results to other publications where it was put before the muscle.

And if understood well, you seem to have submitted a study for publishing and have had it rejected. You should ask more details about why rejected and think about other reasons than this.

Such comparisons very common in surgical literature but very open to many biases/confounders. You will never know if observed differences result from differences in the techniques, patient mix, surgical experience/excellence, institutional variation etc etc

Our gold standard is double blind studies.

For this to be scientifically evidence based, it is necessary for each surgeon to do both techniques on a randomly assigned basis. Then compare the outcomes of each intervention.

Otherwise, logically, we are comparing the outcomes of the surgeons, and NOT of the techniques.

If we are comparing the outcomes of the techniques this is not logically rigorous.

Good Answer Om Prakash Sudrania

My opinion is that you can not compare two different specialities.

If you have to compare the tow, you have to precise the variables. I mean the details, the attitude towards the same situation and difficulties or complications.

Nice Contribution Trevor J D'Netto