The thing is even that is speculative. You cannot know that these treatments specifically worked better. These are things we can only assess via statistics on more than a single patient.
I.E. x% more patient survive after n years while using this or this treatment. And same treatment could increase odds of dying sooner from other decease out of scope with the research years later.
I.E. x% more patient survive after n years while using this or this treatment. And same treatment could increase odds of dying sooner from other decease out of scope with the research years later.