I work in preclinical pharma research, so I have spent a good amount of time trying to recapitulate published data in animal models, so not quite clinical trial

I work in preclinical pharma research, so I have spent a good amount of time trying to recapitulate published data in animal models, so not quite clinical trial data. People who do this work learn how to evaluate trustworthiness. It can be as granular as "this lab is the only one publishing this kind of information, so we'll be skeptical" to a bit more broad "this class of drug isn't expected to have that biology" to "I trust this company over that institution". We route around the fact that some information isn't reliable, and that's not always because of dishonesty or fraud. I'm not a clinician and don't deal with them regularly, but the impression I get is that new studies are published by researchers who have a lot of connections (dubbed thought leaders). They present at conferences. Other clinicians pick up the use case that matches their need (this patient has failed other therapies for this indication, let's try this new thing I'm now aware of). Then as experience grows, clinicians have more nuanced understanding of the use cases for that new information and its reliability. Frustratingly, this can take years, but that's bug that's also a feature.