Eliminating Publication Bias: The Effect of Negative Trial Results

Extract

“Negative results have never made riveting reading,” a 1987 editorialist in the British Medical Journal observed.

Nor have clinical research careers been much advanced through their publication. Perhaps it’s not surprising, then, that several studies have demonstrated the existence of publication bias. Around 20% of studies never have their results published or presented publicly, and of those appearing as meeting abstracts, half are never published in a peer-reviewed journal, said Chris Williams, M.D., coordinator of the Cochrane Cancer Network, Oxford, England.

“There is a strong link between failure to publish and a study being negative,” he said. “At every level the bias in the literature favors seeing things in more of a rosy light than is perhaps true. So there is an in-built potential in meta-analysis to inflate benefit.” Studies with significant positive results are published on average several years sooner than negative studies, and are more likely to appear in prestigious, high-profile journals.