Now the federal government is working hard to raise the standards of evidence, seeking to distinguish between what is effective, useless and harmful or even dangerous.
“The research has been making steady progress,” said Dr. Josephine P. Briggs, director of the National Center for Complementary and Alternative Medicine, a division of theNational Institutes of Health. “It’s reasonably new that rigorous methods are being used to study these health practices.”
The need for rigor can be striking. For instance, a 2004 Harvard study identified 181 research papers on yoga therapy reporting that it could be used to treat an impressive array of ailments — including asthma, heart disease, hypertension, depression, back pain, bronchitis,diabetes, cancer, arthritis, insomnia, lung disease and high blood pressure.
It turned out that only 40 percent of the studies used randomized controlled trials — the usual way of establishing reliable knowledge about whether a drug, diet or other intervention is really safe and effective. In such trials, scientists randomly assign patients to treatment or control groups with the aim of eliminating bias from clinician and patient decisions.
Sat Bir S. Khalsa, the study’s author and a sleep researcher at the Harvard Medical School, said an added complication was that “the vast majority of these studies have been small,” averaging 30 or fewer subjects per arm of the randomized trial. The smaller the sample size, he warned, the greater the risk of error, including false positives and false negatives.
Critics of alternative medicine have seized on that weakness. R. Barker Bausell, a senior research methodologist at the University of Maryland and the author of “Snake Oil Science” (Oxford, 2007), says small studies often have a built-in conflict of interest: they need to show positive results to win grants for larger investigations.
“All these things conspire to produce false positives,” Dr. Bausell said in an interview. “They make the results extremely questionable.”
That kind of fog is what Dr. Briggs and the National Center for Complementary and Alternative Medicine, with a budget of $122 million this year, are trying to eliminate. Their trials tend to be longer and larger. And if a treatment shows promise, the center extends the trials to many centers, further lowering the odds of false positives and investigator bias.
For instance, the center is conducting a large study to see if extracts from the ginkgo biloba tree can slow the progression of Alzheimer’s disease. The clinical trials involve centers in California, Maryland, North Carolina and Pennsylvania and recruited more than 3,000 patients, all of them over 75. The study is to end next year.
Another large study enrolled 570 participants to see if acupuncture provided pain relief and improved function for people with osteoarthritis of the knee. In 2004, it reported positive results. Dr. Brian M. Berman, the study’s director and a professor of medicine at the University of Maryland, said the inquiry “establishes that acupuncture is an effective complement to conventional arthritis treatment.”
In an interview, Dr. Briggs said another good way to improve clinical trials was to ensure product uniformity, especially on herbal treatments. “We feel we have really influenced the standards,” she said.
Over the years, laboratories have found that up to 75 percent of the samples of ginkgo biloba failed to show the claimed levels of the active ingredient. Scientists doing a clinical trial have a large incentive to fix that kind of inconsistency.
Dr. Briggs said such investments would be likely to pay off in the future by documenting real benefits from at least some of the unorthodox treatments. “I believe that as the sensitivities of our measures improve, we’ll do a better job at detecting these modest but important effects” for disease prevention and healing, she said.
An open question is how far the new wave will go. The high costs of good clinical trials, which can run to millions of dollars, means relatively few are done in the field of alternative therapies and relatively few of the extravagant claims are closely examined.
“In tight funding times, that’s going to get worse,” said Dr. Khalsa of Harvard, who is doing a clinical trial on whether yoga can fight insomnia. “It’s a big problem. These grants are still very hard to get and the emphasis is still on conventional medicine, on the magic pill or procedure that’s going to take away all these diseases.”
Comment
This
news was published on September 29, 2008 in The New York Times, and
it was written by William J.Broad.
In
the news they talk about various aspects. The first is a problem that
affects alternative medicine, the frauds. There are two types of
fraud. The first is the false doctors. They are people who pretend to
be experts in alternative medicine therapies such as acupuncture.
This problem exists to a lesser extent the USA because the industry
of alternative medicine is more regulated, there are hospitals
specialized in this branch of medicine. However, in Spain, as it is
not regularized, many people exercise this profession when they
haven't got the necessary qualifications. The second fraud are
distorted or incomplete studies. In the news, it is mentioned trials
which have not been tested by enough people. Because of that, the
results are not real because they produce false positives or false
negatives.
To
try to solve this second problem, Dr. Briggs and the National Center
for Complementary and Alternative Medicine are investigating many of
the studies that have been conducted on alternative medicine to check
that they are correct. The problem is that it takes much money to do
this research and grants are hard to get.
Another
aspect that is mentioned in the text are various treatments that are
not well known in Spain. One very important and that most caught my
attention are the extracts from the ginkgo biloba tree which can slow
the progression of Alzheimer's disease. I think it is very important
to research on this topic because Alzheimer is a disease that affects
more than 600,000 people in Spain. Alzheimer's disease is an
irreversible, progressive disease of the brain that slowly destroys
memory and thinking skills, and eventually even the ability to carry
out the simplest tasks.
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