Industry-funded drug trials are more likely to yield positive results. (Mark Blinch / Reuters )
When weighing the results of a medical study it's important to consider who supplied money to conduct the research. According to an analysis of drug trials published Monday, studies were much more likely to be positive -- that is, showing the drug worked -- in trials that were funded by the pharmaceutical industry.
Researchers reviewed 546 drug trials and found that industry-funded trials reported positive outcomes 85% of the time compared with 50% of the time for government-funded trials and 72% of the time for trials funded by nonprofits or non-federal organizations. Among the nonprofit or non-federal studies, those that received industry contributions were more likely to be positive (85%) compared with those that did not have any industry support (61%).
To be sure, the pharmaceutical industry is more selective in what studies it funds. Drug companies want to know they have a reasonably good chance of success before investing in a study. In contrast, the federal government often funds studies that are at an earlier stage of research when the outcomes are far less certain. But the new study also showed that results of industry-funded studies were published within two years of the study completion 32% of the time compared with 54% for government trials and 56% for nonprofit or non-federal trials.
The paper suggests that ClinicalTrials.gov, a web-based registry of clinical trials established in 1999, is a valuable source of information for documenting study quality especially if a trial sponsor publishes the study protocol in advance of enrolling patients and reports the findings promptly. Doing so prevents manipulating data or selectively publishing some results but not others.
The study was published Monday in the Annals of Internal Medicine. And, although it is not a drug clinical trial, for the sake of transparency let us note that it was funded by the National Library of Medicine and National Institute of Child Health and Human Development.
-- Shari Roan
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