I think you are confused. I never implied it was different material. Blocking you now.

Have you tried to read a primary resource, scientific article? They are mostly behind a paywall, hospitals and universities pay for subscription access. So yes, doctors and researchers have easier access to papers than the public (and the expertise to critically evaluate the information presented). Also, those large cohort studies with thorough stats are a huge amount of work and always have a team of people to design the experiments, interact with patients, get the data, run the stats, and so forth. MDs would be in the mix there too, it’s not like a single immunologist would do the whole thing alone…