I get the impression that much of medicine is one of those strange practices that looks kinda like science, but really isn't. Medical practice appears to work more like a highly evolved guild system than any other kind of recognizable scientific activity. It's probably far beyond the point where its necessary to bring in actual scientific practices, so I can't say it's on the cusp of a sweeping change.
One of the problems that really prevents the change is that analysis of patient data is so highly protected that it's virtually impossible to do proper studies. We assume that people with such access are performing them, but I know from second-hand experience that actual time spent on real treatment studies is very small and most of the time is spent dealing with policy and patient privacy issues.
Large insurance and government-based (VA, CMS, etc.) providers have the most data, but either what they're looking for isn't exactly aligned with what patients need, or the organizations are so fubar (e.g. the VA) that real studies are unlikely to happen.
There really needs to be some kind of research exception/feedback loop on massive scale data analytics that allows some group of objective researchers to mine patient data and put in place actionable recommendations that work their way into medicine rapidly -- perhaps with some penalizing stick insurance providers can leverage against practitioners to make sure they adopt newer better practices.