| |
Consumers
are not the only ones experimenting with complementary
and alternative medicine
these days. After shunning CAM for most of the past century,
many conventionally trained physicians are now working to
assess the worth of nonconventional remedies. Alas, the mission
is not as straightforward as it sounds.
Western science has developed powerful methods for testing
pills and devices, but CAM therapies can pose unique challenges.
Appraising them will require not only new studies but, in
some cases, more sophisticated ways of designing studies.
The gold standard in scientific medicine is a randomized,
placebo-controlled, double-blind trial. If researchers wanted
to test a new pill for heart failure, they would assign patients
at random to receive either the new pill or a placebo pill
that contained no active medicine. Neither the doctors nor
the patients would know which subjects were getting the actual
treatment. After all the results had been collected, the investigators
would determine whether the severity of heart failure was
lower in the group that received the new medicine.
Now imagine conducting a similar study of acupuncture. Unlike
a pharmaceutical drug, acupuncture technique varies among
practitioners. Will participants in the trial receive Chinese
acupuncture, or will they get the Japanese or Korean variety?
Which acupuncture points will therapists target on the patients’
bodies? How far will they insert their needles? Will they
twist the needles or apply electrical currents, or will they
simply apply physical pressure?
The challenges don’t end there. To separate the “acupuncture
effect” from the placebo effect, the researchers will
have to devise a sham procedure that is indistinguishable
from the real one. Should patients in the placebo group have
real needles inserted at a slight distance from the true acupuncture
points? At points used to treat some other condition? Or should
the therapists use sham needles that don’t really penetrate
the skin? And how will the acupuncturists avoid conveying
unconscious clues about whether they’re giving real
treatment? Should the patients be blindfolded? These dilemmas
are not unique to acupuncture. Imagine studying massage therapy
for low-back pain, yoga for fibromyalgia or hypnosis to help
people quit smoking. Each remedy would pose new problems in
study design.
Herb studies are less daunting, but they, too, present challenges.
To design a rigorous echinacea study, researchers would have
to settle on one species of the herb (three are in widespread
use). They would also have to use plants of a specified age,
and decide how to prepare and store them. A liquid extract
might have different effects from dried, crushed leaves.
In many cases, we will need to compare CAM therapies not only
with placebos but also with conventional therapies. Can you
imagine designing a double-blind, placebo-controlled study
comparing acupuncture with pain pills? It could require designing
placebos for both of the active treatments, and administering
four interventions in different combinations. Experts are
now racing to develop new study designs, and their efforts
could open new avenues to good medicine.
Drs.
Ted Kaptchuk, David Eisenberg and Anthony Komaroff,
Harvard Medical School
Dec.
2, 2002, © 2002 Newsweek, Inc.
|