This seems like a pretty useless study as they don't collect any results from human doctors, therefore there is nothing to compare their GPT-4V results to.
> All images were evaluated by two senior surgical residents (K.R.A, H.S.) and a board-certified internal medicine physician (A.T.). ECGs and clinical photos of dermatologic conditions were additionally evaluated by a board-certified cardiac electrophysiologist (A.H.) and dermatologist (A.C.), respectively
In the paper the tasks are only completed by GPT-4V. For a valid scientific investigation, there should be a control set completed by e.g. qualified doctors. When the panel of experts does their evaluation, they should rate both sets of responses so that the difference in score can be compared in the paper.
It assumes that "here are 5 doctors which are always correct". Then measures GPT's correctness against them.