Medical research depends on funding from the private sector, in particular from biotechnology and drug companies, but this funding may lead to conflicts of interest about the results of medical research.
To measure the potential impact of public funding compared to industry funding, researchers analysed the affiliations of authors and the funding sources of the most frequently cited medical research papers from 1994 to 2003. Top-cited papers have a major impact on scientific thinking.
Of the 289 most frequently cited articles, most had at least one author with a university (76%) or hospital (57%) affiliation.
Government or public funding was most common (60% of articles), followed by industry (36%). However, the proportion of articles funded by industry increased over the decade and by 2001, more than 50% of funding came from industry, surpassing funding from government or public sources.
Sixty five of the 77 top-cited randomised controlled trials received funding from industry, whereas government and public sources funded only 32 trials. The proportion of trials funded by industry also increased significantly over time. Eighteen of the 32 most cited trials published after 1999 were funded by industry alone.
Participation of academics in influential medical research has remained strong, despite the perceived crisis in academic medicine, say the authors. Yet industry funds an increasing proportion of this research, especially randomised controlled trials, most of which are now funded exclusively by industry.
They suggest that the role of industry should be scrutinised further. They also believe that medical research should reflect public needs more closely and the efforts of all those involved (government, industry, and academia) should be better coordinated.