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Scientists Design New Placebo Acupuncture Needle
Study Finds Device is of "High Credibility"
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A long-standing point
of contention to the validity of randomized, controlled acupuncture trials
has been the inability of investigators to create and implement a true
placebo, or "sham," acupuncture needle. The crux of this contention has been
that patients know whether they are receiving acupuncture because they can
see or feel a needle being inserted, which gives rise to the placebo effect
and can skew the results of an otherwise sound study. A secondary point to
this argument is that needles cause an effect on subjects whether being
inserted at specific acupuncture points or not, and that this effect, though
unintentional, may produce subjective data, lessening a study's credibility.
Over the years, scientists have tried various methods for mimicking the
sensation of an acupuncture needle, including the sharp end of a pencil; a
practitioner's fingernail; a needle guide tube - even the end of a cocktail
swizzle stick - all without producing the desired effect. Researchers in
Germany may have finally solved this problem with an experimental placebo
needle used as part of a headache study, the results of which have been
published in Forschende Komplement¼rmedizin und Klassiche Naturheilkunde
(Research in Complementary and Classical Natural Medicine).1
Sixty-eight patients with a history of tension-type headache were chosen for
the study. Half were assigned to an acupuncture group; the other half to a
placebo group. Before being assigned, each patient was notified that they
would receive one of two acupuncture treatments, and that it was not known
which type was more effective. At the first treatment, patients were told
that they might feel a pricking sensation from the needle, and that the de
qi sensation could occur after the needle was inserted. Patients in the
placebo group were further told that the needles would only be inserted
gently and superficially, which would require the use of a small cube to
keep them in place.
The placebo needle used in the study consisted of a real acupuncture needle
(#16, 30 x 0.3 millimeters), with the tip removed and a new tip rounded off
with a diamond polisher so as to touch, but not puncture, the skin. A
cube-shaped block of sterilized foam was used as a holding device for the
needle, with a ring of adhesive tape affixed to bottom of the foam to hold
it in place on the skin. By inserting the needle through the foam, the view
of the volunteers would be blocked such that they would not know whether the
needle had actually penetrated the skin. In addition, once the needle
touched the skin, it was gently twisted by the practitioner to enhance the
illusion of treatment.
Patients in both groups received two treatments per week for five weeks, and
received acupuncture bilaterally at the same points (GB20, LI4, LR3 and
TW5). In the placebo group, needles were inserted, manipulated and left in
place for 30 minutes, using a total of eight placebo needles per session. In
the true acupuncture group, slightly different needles were used (#8, 0.3 x
0.3 millimeters or #2, 0.2 x 0.15 mm) and were also left in place for 30
minutes after insertion.
To determine the credibility of the placebo needles, the investigators
subjected the volunteers to a three-part questionnaire. The first section
asked patients about their interest in and knowledge of acupuncture; the
second section focused on the patients' acceptance of acupuncture as a
treatment for headache; and the third section measured the credibility and
expectations of the patients toward the actual treatment. To test
credibility, the patients filled in the third part of the questionnaire
after the first treatment. After four or five treatments, patients were then
asked to state whether they felt the needle being inserted and whether they
had felt the de qi sensation.
Researchers Find "No Significant Differences" between Treatments
Sixty-four patients answered the questionnaire. After tabulating the
results, the scientists found "no significant differences" between the
groups' responses in any section. In the interest section, the difference
between the true and placebo acupuncture groups was two-hundredths of a
point; in the general acceptance section, the difference was
seven-hundredths of a point; and in the credibility section, the difference
was less than half a point.
The placebo needle fared nearly as well when patients were asked about
needle insertion and de qi sensation. Every patient in the true acupuncture
group said they felt the needle being inserted; 28 patients in the placebo
group said they also reported a feeling of needle insertion. The fact that
the experimental needle design was able to fool more than 87% of the
patients in the placebo group into thinking they had been needled shows that
it was quite effective in achieving its intended goal as a placebo. Although
the experimental design did not work as well as a true acupuncture needle,
the researchers felt this was due to the placebo needles being pressed down
differently than real needles. They added that "this problem can ， be
overcome by adequate training with the placebo needle."
In addition, only 34% of those in the placebo group reported feeling the de
qi sensation compared to more than 80% of those receiving true acupuncture.
Furthermore, although the placebo needles never punctured the skin, they
retained the illusion that they were inserted for the duration of treatment.
The scientists reported that there were no instances of "spontaneous
removal," or a needle falling out from its location, during the study.
The fact that more than a third of patients treated with the placebo needle
experienced de qi did raise some concerns among the scientists, who said
that the results of their experiment "， call into question the main claim of
placebo needles that they only are eliciting a placebo response." To avoid
producing the de qi response, they proposed that future studies use non-acupoints
for placebo needling.
Needle Shows Great Potential for Use in Future Studies
Unlike most acupuncture studies, which are performed to measure the effects
of treatment for a particular condition, the aim of the German study was to
judge the credibility of a placebo needle that could be used in later
studies. The scientists stopped short of calling their design a complete
success, but believe their results show that the experimental needle "is of
high credibility" and provides acceptance by patients "similar to that of
real acupuncture."
While the outcome of the German study has yet to be confirmed independently,
the experimental needle holds tremendous promise for the future of
acupuncture and Oriental medicine. If the needle design fares as well in
future tests, it could revolutionize the way acupuncture trials are
conducted in the U.S. and elsewhere. As the scientists noted in their
conclusion, "preparing the needle is easy and does not require any special
technical appliance," meaning that it can be used quickly and without much
training. In addition, the researchers noted that "compared with other
placebo needles, it is certainly the most economical" product available,
which would reduce the costs of future studies. Finally, and perhaps most
importantly, it could pave the way for the next generation of researchers to
produce what the medical and insurance industries have claimed the Oriental
medicine profession would never be able to deliver -- randomized, large
scale, placebo-controlled clinical investigations that provide convincing
evidence of the safety and effectiveness of acupuncture.
Reference
1. Fink M, Gutenbrunner C, Rollnik J, et al. Credibility of a newly designed
placebo needle for clinical trials in acupuncture research. Forschende
Komplement¼rmedizin und Klassiche Naturheilkunde 2001;8(6):368-72. Available
online at www.karger.com/journals/fkm.
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Acupuncture Today by fax (714-899-4273) or e-mail (Editorial@AcupunctureToday.com).
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Information resource:
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