A third of published medical trials have come up with a false conclusion-usually one that favours the drug or therapy being reviewed. In other words, there's no scientific proof that many of the drugs we take are effective or safe.
The best-known example of data 'misrepresentation' concerns the antiviral drug, Tamiflu (oseltamivir), which was considered an effective treatment against influenza A and B viruses. But other researchers who reanalysed the data discovered its effectiveness had been overstated and its side effects downplayed.
Researchers from Stanford University School of Medicine took another look at the data used in 38 published randomised clinical trials, considered the 'gold standard' of medical research-and found that 35 per cent came to conclusions that weren't supported by the data. Most of the studies were paid for by the manufacturer of the drug being assessed.
It wasn't just drugs that were shown in a better light by researchers. One therapy, sclerotherapy, which treats enlarged and bleeding veins in the esophagus, reduces mortality but doesn't stop the bleeding, the original study concluded. But on renalaysing the data, the Stanford researchers found exactly the opposite: the therapy stopped the bleeding but didn't affect the rate of death.
(Source: Journal of the American Medical Association, 2014; 312 (10): 1024)