01/04/2012 11:39 EST | Updated 03/05/2012 05:12 EST

UK experts: Drug studies being suppressed by researchers, could hurt patients

LONDON - A British medical journal says a worrying number of drug studies are being suppressed by researchers and that the lack of public data could threaten patient safety.

One study described by the BMJ journal found the results of fewer than half of drug trials paid for by the U.S. National Institutes for Health were published in a scientific journal within 30 months of being finished.

The U.S. agency spends about $3.5 billion sponsoring more than 100,000 clinical trials worldwide.

Previous studies have found one quarter to one half of clinical trials are unpublished for various reasons, including companies sitting on information that could hurt sales, journals uninterested in publishing negative results and academics fearful of releasing results that contradict their original hypothesis.