Repeat after me: Sham = placebo

Yesterday I mentioned Linde et al.'s 2009 Cochrane review and how the authors noted that having needles  anywhere on the skin is as effective as sticking them in the "official" acupuncture points. Here's a recent news item on their eureka discovery:

The researchers conducted two sets of tests on patients with chronic migraine pain. In one test, acupuncture needles were applied in strict adherence with established practice. But in the other test, the needles were inserted either in the wrong positions or else the needles did not penetrate the skin at all.

And as the authors concluded: "Collectively, the studies suggest that migraine patients benefit from acupuncture, although the correct placement of needles seems to be less relevant than is usually thought by acupuncturists."

Lead author Klaus Linde explains these results:

Much of the clinical benefit of acupuncture might be due to non- specific needling effects and powerful placebo effects, meaning selection of specific needle points may be less important than many practitioners have traditionally argued.

Well that's a clarification/qualification I'm more comfortable with. Noting that the observed reduction in headaches are due to "non-specific needling effects" and "powerful placebo effects" calms me down.

Let's be clear that the placebo group is there for comparison. If and when the experimental group does not perform any better than the control group then the conclusion ought to be: the modality under test isn't effective. If acupuncturists tell us that the needles should break the skin and that certain points need to be manipulated instead of others in the the treatment of condition X, and if the sham procedure does not meet these criteria, and if there is no statistically significant difference in the results between the two procedures then the conclusion is simple: acupuncture doesn't work.

Sure, we can do a comparative test of placebos and find out which are comparable to placebo X and which elicit placebo effects better than others. But let's keep in mind that they're placebos.

The picture that's coming out of acupuncture studies is that needling anywhere and even jabbing without penetrating the skin (unbeknownst to the particpants of course) all elicit similar or the same effects. One wonders then whether touching, pinching, fondling, scratching, spanking, "hickey-ing," licking, tapping, ... would likewise trigger the same. The only problem is blinding the participants as to which procedure they're receiving. I would guess, however, that being kissed, licked, and fondled by persons the participant finds "interesting" would have much greater, uhh, clinical benefit than being poked with needles.