ITM, I agree, however, I also thought we were looking for a...

ITM, I agree, however, I also thought we were looking for a reason for the placebo effect> Surely this seems relevant to me.
here is the last part
.....
Most of the patients in the study said afterward that they had expected to get a big boost from the more expensive drug and were simply amazed at the result.
There is a scientific explanation for this, says Espay, as a placebo effect can spur the release of brain dopamine, which is depressed by Parkinson's. If you can manage the placebo effect, he says, you can make a positive difference in patients' lives.
"If we can find strategies to harness the placebo response to enhance the benefits of treatments, we could potentially maximize the benefit of treatment while reducing the dosage of drugs needed and possibly reducing side effects," Espay said in a statement.
The new study, though, demonstrates again just how risky it is designing studies for diseases of the brain. If the average person enrolled in a CNS drug trial can expect to get a boost from the experimental drug--factoring in the chance that they may be getting nothing but a sugar pill--the data collected can be skewed by just those expectations. And there are scores of researchers in the depression field who would attest to that. Finding a way around the placebo effect is attracting more attention among developers who haven't abandoned the field. Learning how to manage benefits from it sounds like quite a challenge....

Could the extra attention paid to the trialists, and their active participation not have affected the results in a positive way?

This is from my perspective, as lay person, regards K