Clinical trials results linked to funding

SCIENTISTS who carry out clinical trials for private drug companies are more likely to report positive outcomes than authors of studies carried out for not-for-profit organisations.

A review of clinical trials published in the British Medical Journal (BMJ) suggests the funding of a drug trial appears to influence the outcome.

Danish researchers studied 159 trials published between 1997 and 2001 in the BMJ - which obliges authors to declare their funding and any conflict of interest.

The reviewers from Copenhagen University Hospital in Denmark

assessed the impact of personal, academic and political influences in addition to funding on the conclusions reached by authors of clinical trials.

“Authors’ conclusions were not significantly different in trials without competing interests, trials with other competing interests or trials funded jointly by profit and non-profit organisations,” they noted.

“However in both pharmacological and non-pharmacological trials funded by profit organisations, the author’s conclusions were positively associated with financial competing interests - a significant proportion of author conclusions in these trials favoured experimental intervention.”

They also stressed that as the BMJ requires authors to report their competing interest, some authors may have chosen not to submit their paper to the journal.

“If this is the case the researchers conclude that the study may actually underestimate the extent of association between competing interests and authors’ conclusions.”

While the Danish reviewers note that drug companies could be either luckier or more skilful in choosing which trials to back, they point out that the results of their study did not find any evidence of poor methodology or other technical problems in the studies which favoured the drug.

Neither did their review find any significant association between personal, academic, or political competing interests and the authors’ conclusions.