Reducing dissemination bias

To address this problem, an EU-funded project, 'Overcome failure to publish negative findings' (OPEN), aimed to develop evidence-informed recommendations focused on reducing dissemination bias.

The first phase of the project involved systematic reviews to identify the current evidence on dissemination bias. This step also included a review of the literature to clarify terminology used to describe various aspects of dissemination bias.

During the second phase, researchers sent out surveys to various groups of key stakeholders to assess their awareness of the problem and steps they had taken to address it. Stakeholders included funding agencies, the pharmaceutical industry, research ethics committees, research institutions, researchers, trial registries, journals and regulatory agencies.

The survey results showed that while many stakeholders have policies in place to prevent dissemination bias, most find it difficult to enforce them. For example, 68 % of funding agencies said they had a policy, but less than half actively follow up with grantees. Journal editors noted their reluctance to require trial registration and their preference for publishing positive trials. The survey did find, however, that the European Medicines Agency (EMA) has launched a website, with the goal of improving transparency.

After compiling survey findings, the OPEN team sponsored a recommendations workshop. Of the 70 recommendations put forth by the project, 47 tailored to key groups were jointly agreed on, along with 4 general recommendations. All the recommendations aim to strengthen policies, facilitate implementation and increase transparency.

These findings have been disseminated through OPEN's website, journal publications and presentations at scientific meetings. By raising awareness of this issue, the team hopes to facilitate a change in practice, leading to less dissemination bias.

This outcome will improve knowledge about clinical trials so that apparent drug efficacy is not inflated. As a result, it will be easier to distinguish effective drugs from ineffective ones and to see what treatments could cause harm. Clearly, patients will benefit from a more comprehensive and unbiased evidence base.