When there are financial ties between researchers working on a clinical study and the drug industry, the data from these tests are more likely to be positive, according to a new report in The BMJ, as more than half of principal investigators were found to have been given money by biopharma.
A team of U.S. researchers writing in the prestigious U.K. medical journal said that when money changed hands between the two, this was “independently associated with positive trial results, suggesting bias in the evidence base.”
This sort of correlation has been observed before and the authors note that there is of course a common and longstanding financial tie between the industry and many investigators of RCTs.
The authors say however that studies investigating these relationships in the past “have been conflicting.”
So, they set up their own study on the connection between financial ties of principal investigators and study outcomes in a random sample of 195 drug trials published back in 2013.
The team looked at trials that were focused in on the effectiveness of drugs, given that these studies have a bigger impact on both clinical practice as well as healthcare costs.
In their report, they found that more than half (58%) of these investigators had financial ties to the drug industry. These included, they note, travel expenses, honorariums, payment for advisory work, or stock ownership.
It said when it drilled down into the data, the results “show that trials authored by principal investigators with financial ties to drug manufacturers were more likely than other trials to report favourable results.”
The authors point to possible mechanisms linking industry funding, financial ties, and trial results such as “bias by selective outcome reporting, lack of publication, and inappropriate analyses.”
The analysis is only observational, and the authors note caution on interpretation and warn that it cannot be used to draw conclusions about causation, adding that “More thought needs to be given to the roles that investigators, policy makers, and journal editors can play in ensuring the credibility of the evidence base.” They urge for the need for greater transparency in the future to try to make these data clearer.