The breaking of blinding and contrary measurements is enough to undermine most claims for placebo.
"Ah, people with pain. One group will get nothing and the other a placebo."
Reminds me of the old joke, where a respected scientist is announcing he has some great cure for the disease of the day and is presenting the impressive results to an audience, when someone pipes up and asks:
'How did this compare to the control group?'
The presenter is indignant and says, "Excuse me? You're asking if I randomly selected half of these poor souls to be deprived of the medicine, just to see what would happen to them?"
'...yes.'
"Of course not! That would have condemned half of them to an avoidable death!"
'...but which half?'
not that I was proposing such a study - I was asking if we have already done them and what the data says if we have.
(Not a real site, just riffing off whydoesntgodhealamputees.com.)
Following is the assumption that, while we have learned a lot recently, the total map of mind/body connections is enormously larger than our current understanding of it.
So, it seems possible to me that the placebo effect can have real, physical and measurable effects on a human body, given the above assumptions.
One way or another, decades of research of, to varying degrees, confirmed this connection, though we haven't made much progress in understanding the underlying mechanisms of action.
- A placebo pills and a nice, empathic, optimistic doctor - No pills and a nice and empathic doctor - A placebo pills and a cold and pessimistic doctor - No pills and a cold and pessimistic doctor
The pills have practically no effect at all, doctor behavior can have a measurable impact.
Besides I don't think there is a proven effect of placebo for other than psychosomatic symptoms (in particular pain and depression symptoms).
What matters is not that subjective feelings do improve?
https://www.amazon.com/Consciousness-Brain-Deciphering-Codes...
Like, I really don't see any way of avoiding this in psychology and neuroscience (and indeed even if possible, it might not be a good idea).
These sorts of experiments are helping with making prognoses of whether a patient recovering from a coma will remain in a vegetative state, or if they'll regain consciousness in time.
Placebo just refers to the bundled biases and other uncontrolled-for influences. It is not a real thing that can be used to make anyone actually better. Whenever there is a physical measurement that can be made about some affected body function, the placebo effect mysteriously disappears.