I think the distinction is that a lot of the time, the placebo effect can be explained away as the result of reporting bias rather than any "real" observable effect. That's what I meant by it being explainable in psychological/psychiatric studies (where measurements of the efficacy of the treatment rely on patients' own reported experience) and in studies where the double-blind is flawed (and the outcome relies on judgements made by the scientists who will tend to have a fairly specific expectation of result, e.g. biopsy or x-ray results).
In those trials where double-blinding seems reasonable and there is still a placebo effect, it is scientifically plausible (in some cases) to discount any observed effect as being coincidental. That is, we don't entirely know what "causes" a disease and it is known that some disease go into remission despite the absence of any apparent change in conditions. For example, it doesn't seem magickal/mystical/parapsychological to me to say that sometimes the body overcomes disease without any assistance.
I'd love to be able to accept that belief plays a causal role in such situations but to my mind there is not yet sufficient evidence to overcome my unfortunately necessary scepticism. I accept it is possible but I want to see objective evidence.
Anyways, to directly address your comment Lurid, I think that the general consensus in the medical community is that the placebo effect is simply the result of patients getting better naturally. This is why doctors around the world aren't exclaiming "OMG! we don't need chemotherapy to treat cancer, we just have to make patients *believe* they will get better and the placebo effect will do the rest!"
I am aware of observations that the effect seems greater when medics wear white coats/use needles etc. but what is needed here is a study of a single population where patients are given different types of placebos (one cannot compare between studies due to population differences). Are you familar of any such studies? |
