In light of a number of recent drug development and marketing controversies, there is increasing public focus on the role of industry in determining how drugs are used.1–3 New methods that evaluate how funding has influenced the design, reporting, and synthesis of evidence from clinical trials have identified the breadth of industry involvement in evidence production. The downstream effects on public health remain difficult to quantify. In order to identify and mitigate the potential effects of any one type of trial sponsor, we argue that these new methods should now be used routinely and systematically, in a process we call evidence surveillance.

Impact of industry on medical practice

There is compelling evidence that the pharmaceutical industry can influence clinical practice. A handful of notable cases illustrate some of the tactics employed by industry to ensure market uptake and widespread use of its products. The rofecoxib (Vioxx) case demonstrates how diluting the evidence base with positive reports may have led to the prolonged use of the drug and may have caused tens of thousands of additional heart attacks and strokes in the USA alone.2 Other examples of translation problems occurred with rosiglitazone (Avandia), where industry affiliation was associated with more favourable conclusions about cardiovascular risk,4 and oseltamivir (Tamiflu), where unpublished and previously inaccessible trial results may hold information about serious adverse effects related to its use.3

These examples suggest that our system of evidence production and translation remains susceptible to the agendas of drug-makers, which may not …