This is precisely why the only valid medical studies are double-blind studies. When the doctors don't even know which treatment is real vs. placebo you get more reliable results. This tells me that those administering the trial treatments knew which patients were getting placebos and which were getting the real deal. Emotions get in the way of things, and when doctors know which is which they have a tendency to surreptitiously move those they feel are more in need out of the control group. This throws all reliability of the study out the window.