"irrefutable data" is always a concern in the medical community, not so much for the FDA...at what point do large bodies of anecdotal evidence segue into "acknowledged evidence"...putting aside the FDA for a moment and their impact on release/use/approval of drugs...there was a time when the FDA DIDN'T exist but doctors through observation and trialing doses were able to see IRREFUTABLE evidence..that if it walked, talked and waggled like a duck...it was unlikely to be a camel.