davidstarlingm wrote:But you're absolutely right: the total relaxation from getting knocked out for half an hour could very easily overwhelm any difference in the immediate pain relief.
Which, as with sham acupuncture (some of which does involve things like retracting needles, so it still feels the same but doesn't involve the actual puncture part), is why you compare the intervention to placebo, rather than to doing nothing at all.
If anesthetic with and without chiropractic manipulation has the same effect, we can conclude that the manipulation isn't what caused it.
If feeling the poke of a bunch of needles has the same effect whether or not any puncturing happens, we can conclude that the puncturing isn't what caused it.
If taking a pill has the same effect whether or not there's anything inside, we can conclude that whatever's inside isn't what caused it.
Sure, proponents of the intervention will claim this still shows efficacy, but people doing real clinical research know that no advantage over placebo implies no advantage from whatever one thing
differed between the two groups.
A more extreme example of this sort of "therapeutically active placebo" can be found in certain cancer treatment studies. Because it would be unethical to take anyone off treatment completely, what they do is continue treating everyone with whatever they're already on, and then add the experimental therapy or a placebo on top of that, to see if there's a difference in outcome. Of course everyone is still getting better or holding state largely because of the treatment they're already getting, but you can still test whether the additional therapy has any additional effect or not.
(This wouldn't, of course, work with some magical treatment that only works in the absence of any other treatment, but I'm confident enough that no such treatment exists to be okay with the risk of passing it over in the interest of not taking cancer patients off treatment entirely in the interest of testing for it.)
Unless stated otherwise, I do not care
whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
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