Harry Bosk receives an acupuncture treatment for a pulled calf muscle from Marcos Y. Hsu, a licensed acupunturist at the University of Maryland School of Medicine, Center for Integrated Medicine. (Lloyd Fox/Baltimore Sun)

In a 1998 speech, Harkin described watching acupuncture and acupressure ease the pain and violent hiccups of a brother dying of thyroid cancer.

"These are things I have seen with my own eyes," said Harkin, who also lost three other siblings to cancer. "When I see things like this I ask, 'Why? Why aren't these things being researched?'"

A few months later, NCCAM was created through a dozen or so paragraphs added to a budget bill.

The center's main mission was clear: Study alternative therapies and how they could be integrated into conventional treatment.

Because of its origins and purpose, NCCAM has a duality not often found in scientific institutions.

"They are serving two very different masters," said Art Caplan, a bioethicist at the University of Pennsylvania. "At the end of the day, they don't want to turn themselves into 'the institute for showing complementary and alternative medicine is bogus.' Then no one will support them who is pro-complementary and alternative medicine."

Briggs said she has not been subjected to any political pressure in her tenure.

$34 billion business

Americans spend about $34 billion each year out of pocket on complementary and alternative therapies, according to a national survey conducted in 2007 by the U.S. Centers for Disease Control and Prevention.

The survey found that about 40 percent of American adults reported using some sort of alternative treatment in the previous year. Mostly they reported taking supplements; practicing deep breathing exercises; going to a chiropractor or osteopath for spinal manipulation; meditating; or getting massages.

Finding out through well-designed scientific studies whether these treatments work is a valuable service, said neurologist Dr. Steven DeKosky, who sits on the NCCAM advisory council and is dean of the University of Virginia medical school.

"I don't know who else would do that other than NCCAM," he said.

DeKosky headed a $36.5 million study, including $25 million from NCCAM, on ginkgo biloba, a popular supplement taken as a defense against dementia and Alzheimer's disease. DeKosky's study concluded that it did not lower the overall incidence rate of either condition in elderly people who were normal or already had mild cognitive impairment.

The Tribune found that when studying dietary supplements like ginkgo biloba, NCCAM evaluates the results in a way that is accepted within the medical research community.

It's well known that people who receive any treatment, even if it is inert or useless, are likely to report that it makes them feel better. Because scientists don't want to mistake that boost for a real treatment effect, well-designed clinical trials give some volunteers the real therapy and some a fake version of it, then compare the two groups.

NCCAM considers studies finding that a supplement does no better than a placebo to be evidence that it does not work. In an interview with the Tribune, NCCAM director Briggs cited a recent study of the fruit extract of the saw palmetto plant, which found that men who had difficulty urinating because of enlarged prostates reported relief from both the saw palmetto and the fake supplement.

Briggs described the study as one that came back "very convincingly negative" because "it did not demonstrate any benefit over placebo."

But when looking into "mind and body" medicine, NCCAM often argues that a treatment is valuable if patients report that it helped them, even if others receiving a sham treatment said the same. According to Briggs, "most in the mind and body area have actually shown impact."

For example, the center has spent millions of dollars on studies of acupuncture, in which tiny needles are inserted shallowly into the body. NCCAM's website states that the "vital energy" called qi "can be unblocked, according to (traditional Chinese medicine), by using acupuncture at certain points on the body."

Many studies, including those funded by NCCAM, find that true acupuncture performs no better than when a person is fooled into thinking he is getting acupuncture through the use of placebos like retractable needles or even toothpicks twirled on the skin.