Drugmaker-funded science isn't always more likely to favor new medicines than studies paid for by non-profits, according to a new report on past research in rheumatoid arthritis.

The finding flies in the face of a large body of evidence showing industry studies tend to promote new drugs and downplay potential side effects.

That potential bias has fueled concerns that medical care could be guided by warped science, not least because more and more research is being done or paid for by companies with money riding on the results.

The new report, published in the journal Arthritis & Rheumatism, shows 37 of 49 drug trials funded exclusively by manufacturers had positive results. When non-profits such as the government or a foundation picked up the tab, 11 of 16 trials found the studied drug to be effective.

That difference -- seven percent -- is too small to be statistically reliable, meaning that a trial's outcome didn't depend on who sponsored it.

Still, Dr. Nasim Khan, who led the new work, was quick to add a caveat.

"A single study limited to (clinical trials in a single disease) is insufficient to completely dispel worries about potential for bias when financial conflicts of interest exist," Khan, of the University of Arkansas for Medical Sciences in Little Rock, told Reuters Health by email.

Other experts were intrigued by the new data.

"It's an interesting finding, there is no question," said David J. Rothman, who heads the Center for the Study of Society and Medicine at Columbia University in New York and has studied conflicts of interest in medicine.

"It would be nice if industry studies were not biased as the literature suggests," he told Reuters Health. "Nobody wants to demonize the industry."
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